diff --git a/amumal/.env.example b/amumal/.env.example
index 9b05fa9..1aeb648 100644
--- a/amumal/.env.example
+++ b/amumal/.env.example
@@ -1,11 +1,18 @@
-DB_URL=
+DB_HOST=
+DB_NAME=
 DB_USERNAME=
 DB_PASSWORD=
+
 SERVER_URL=
 
 JWT_SECRET=
+
 MAX_FILE_SIZE=
 MAX_REQUEST_SIZE=
-POSTS_FILE_ACCESS_PATH=
-PROFILE_FILE_ACCESS_PATH=
-SERVER_URL=
\ No newline at end of file
+
+AWS_ACCESS_KEY=
+AWS_SECRET_KEY=
+AWS_REGION=
+AWS_S3_BUCKET=
+
+DDL_AUTO_SET=
\ No newline at end of file
diff --git a/amumal/build.gradle b/amumal/build.gradle
index 839f33f..664dc7e 100644
--- a/amumal/build.gradle
+++ b/amumal/build.gradle
@@ -41,6 +41,9 @@ dependencies {
 	// BCrypt
 	implementation 'org.springframework.security:spring-security-crypto'
 
+	// Redis
+	implementation 'org.springframework.boot:spring-boot-starter-data-redis'
+
 	// QueryDSL
 	implementation 'com.querydsl:querydsl-jpa:5.0.0:jakarta'
 	annotationProcessor "com.querydsl:querydsl-apt:5.0.0:jakarta"
@@ -49,6 +52,9 @@ dependencies {
 
 	// Swagger (springdoc-openapi)
 	implementation 'org.springdoc:springdoc-openapi-starter-webmvc-ui:3.0.2'
+
+	// AWS S3
+	implementation 'software.amazon.awssdk:s3:2.26.0'
 }
 
 tasks.named('test') {
diff --git a/amumal/src/main/java/com/kbt/amumal/AmumalApplication.java b/amumal/src/main/java/com/kbt/amumal/AmumalApplication.java
index 356edda..398a0c2 100644
--- a/amumal/src/main/java/com/kbt/amumal/AmumalApplication.java
+++ b/amumal/src/main/java/com/kbt/amumal/AmumalApplication.java
@@ -4,10 +4,13 @@
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.data.jpa.repository.config.EnableJpaAuditing;
 
+import java.util.TimeZone;
+
 @SpringBootApplication
 @EnableJpaAuditing
 public class AmumalApplication {
 	public static void main(String[] args) {
+		TimeZone.setDefault(TimeZone.getTimeZone("Asia/Seoul"));
 		SpringApplication.run(AmumalApplication.class, args);
 	}
 }
diff --git a/amumal/src/main/java/com/kbt/amumal/domain/auth/controller/AuthController.java b/amumal/src/main/java/com/kbt/amumal/domain/auth/controller/AuthController.java
index 95d0b3d..fd70cc7 100644
--- a/amumal/src/main/java/com/kbt/amumal/domain/auth/controller/AuthController.java
+++ b/amumal/src/main/java/com/kbt/amumal/domain/auth/controller/AuthController.java
@@ -9,29 +9,72 @@
 import io.swagger.v3.oas.annotations.tags.Tag;
 import jakarta.validation.Valid;
 import lombok.RequiredArgsConstructor;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.ResponseCookie;
+import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.*;
 
 import java.util.Map;
 
-@Tag(name = "인증", description = "로그인·로그아웃 API")
+@Tag(name = "인증", description = "로그인·로그아웃·토큰 재발급 API")
 @RestController
 @RequiredArgsConstructor
 @RequestMapping("/auth")
 public class AuthController {
+
     private final AuthService authService;
 
-    @Operation(summary = "로그인", description = "이메일·비밀번호로 로그인하고 JWT 액세스 토큰을 반환합니다.")
+    @Operation(summary = "로그인", description = "이메일·비밀번호로 로그인합니다. Access Token은 body, Refresh Token은 HttpOnly 쿠키로 반환됩니다.")
     @SecurityRequirements
     @PostMapping("/")
-    public ApiResponse<?> login(@Valid @RequestBody AuthReqDTO.LoginReq request) {
-        String userInfo = authService.userLogin(request);
+    public ResponseEntity<ApiResponse<?>> login(@Valid @RequestBody AuthReqDTO.LoginReq request) {
+        AuthService.LoginResult result = authService.userLogin(request);
+
+        ResponseCookie refreshCookie = buildRefreshCookie(result.refreshToken(), 30L * 24 * 60 * 60);
 
-        return ApiResponse.success("로그인 성공", Map.of("accessToken", userInfo));
+        return ResponseEntity.ok()
+                .header(HttpHeaders.SET_COOKIE, refreshCookie.toString())
+                .body(ApiResponse.success("로그인 성공", Map.of("accessToken", result.accessToken())));
+    }
+
+    @Operation(summary = "Access Token 재발급", description = "HttpOnly 쿠키의 Refresh Token으로 새 Access Token을 발급합니다.")
+    @SecurityRequirements
+    @PostMapping("/refresh")
+    public ApiResponse<?> refresh(
+            @CookieValue(name = "refreshToken", required = false) String refreshToken) {
+        String newAccessToken = authService.refresh(refreshToken);
+        return ApiResponse.success("토큰 재발급 성공", Map.of("accessToken", newAccessToken));
     }
 
-    @Operation(summary = "로그아웃", description = "토큰 유효성을 검증합니다. 실제 토큰 삭제는 클라이언트에서 처리합니다.")
+    @Operation(summary = "로그아웃", description = "Refresh Token을 Redis에서 삭제하고 쿠키를 만료시킵니다.")
     @PostMapping("/delete")
-    public ApiResponse<?> logout(@LoginUserId int userId) {
-        return ApiResponse.success("로그아웃 성공", null);
+    public ResponseEntity<ApiResponse<?>> logout(@LoginUserId int userId) {
+        authService.logout(userId);
+
+        // maxAge=0 으로 쿠키 즉시 만료
+        ResponseCookie expiredCookie = buildRefreshCookie("", 0);
+
+        return ResponseEntity.ok()
+                .header(HttpHeaders.SET_COOKIE, expiredCookie.toString())
+                .body(ApiResponse.success("로그아웃 성공", null));
+    }
+
+    /**
+     * Refresh Token 쿠키 빌더
+     * - HttpOnly: JS 접근 차단
+     * - Secure: HTTPS 전용
+     * - SameSite=None: 크로스 도메인 허용
+     * - Domain=.amon.p-e.kr: 서브도메인 간 쿠키 공유
+     * - Path=/auth: 토큰 갱신·로그아웃 경로에만 전송
+     */
+    private ResponseCookie buildRefreshCookie(String value, long maxAgeSeconds) {
+        return ResponseCookie.from("refreshToken", value)
+                .httpOnly(true)
+                .sameSite("None")
+                .secure(true)
+                .domain(".amon.p-e.kr")
+                .path("/")
+                .maxAge(maxAgeSeconds)
+                .build();
     }
-}
+}
\ No newline at end of file
diff --git a/amumal/src/main/java/com/kbt/amumal/domain/auth/service/AuthService.java b/amumal/src/main/java/com/kbt/amumal/domain/auth/service/AuthService.java
index b61658d..312a4fa 100644
--- a/amumal/src/main/java/com/kbt/amumal/domain/auth/service/AuthService.java
+++ b/amumal/src/main/java/com/kbt/amumal/domain/auth/service/AuthService.java
@@ -7,17 +7,28 @@
 import com.kbt.amumal.global.error.ErrorCode;
 import com.kbt.amumal.global.util.JwtUtil;
 import lombok.RequiredArgsConstructor;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.data.redis.core.StringRedisTemplate;
 import org.springframework.security.crypto.password.PasswordEncoder;
 import org.springframework.stereotype.Service;
 
+import java.time.Duration;
+
 @Service
 @RequiredArgsConstructor
 public class AuthService {
+
     private final UserRepository userRepository;
     private final JwtUtil jwtUtil;
     private final PasswordEncoder passwordEncoder;
+    private final StringRedisTemplate redisTemplate;
+
+    @Value("${jwt.refresh_expiration_time}")
+    private long refreshExpTimeMs;
 
-    public String userLogin(AuthReqDTO.LoginReq request) {
+    private static final String REFRESH_PREFIX = "RT:";
+
+    public LoginResult userLogin(AuthReqDTO.LoginReq request) {
         User loginUser = userRepository.findByEmail(request.email())
                 .orElseThrow(() -> new CustomException(ErrorCode.LOGIN_FAILED));
 
@@ -25,7 +36,41 @@ public String userLogin(AuthReqDTO.LoginReq request) {
             throw new CustomException(ErrorCode.LOGIN_FAILED);
         }
 
-        // 로그인 성공 시 JWT 발급
-        return jwtUtil.createAccessToken(loginUser.getId(), loginUser.getEmail());
+        String accessToken = jwtUtil.createAccessToken(loginUser.getId(), loginUser.getEmail());
+        String refreshToken = jwtUtil.createRefreshToken(loginUser.getId(), loginUser.getEmail());
+
+        // 유저당 Refresh Token 1개만 유지 (기존 토큰 덮어쓰기 → 메모리 절약)
+        redisTemplate.opsForValue().set(
+                REFRESH_PREFIX + loginUser.getId(),
+                refreshToken,
+                Duration.ofMillis(refreshExpTimeMs)
+        );
+
+        return new LoginResult(accessToken, refreshToken);
     }
+
+    public String refresh(String refreshToken) {
+        if (refreshToken == null || refreshToken.isBlank()) {
+            throw new CustomException(ErrorCode.TOKEN_MISSING);
+        }
+
+        // 만료·위변조 시 GlobalExceptionHandler가 TOKEN_EXPIRED / TOKEN_INVALID 반환
+        jwtUtil.validateToken(refreshToken);
+
+        int userId = jwtUtil.getId(refreshToken);
+        String email = jwtUtil.getEmail(refreshToken);
+
+        String savedToken = redisTemplate.opsForValue().get(REFRESH_PREFIX + userId);
+        if (savedToken == null || !savedToken.equals(refreshToken)) {
+            throw new CustomException(ErrorCode.TOKEN_INVALID);
+        }
+
+        return jwtUtil.createAccessToken(userId, email);
+    }
+
+    public void logout(int userId) {
+        redisTemplate.delete(REFRESH_PREFIX + userId);
+    }
+
+    public record LoginResult(String accessToken, String refreshToken) {}
 }
diff --git a/amumal/src/main/java/com/kbt/amumal/domain/comment/repository/commentRepository.java b/amumal/src/main/java/com/kbt/amumal/domain/comment/repository/commentRepository.java
index ed2959b..3c7f794 100644
--- a/amumal/src/main/java/com/kbt/amumal/domain/comment/repository/commentRepository.java
+++ b/amumal/src/main/java/com/kbt/amumal/domain/comment/repository/commentRepository.java
@@ -1,13 +1,19 @@
 package com.kbt.amumal.domain.comment.repository;
 
 import com.kbt.amumal.domain.comment.entity.Comment;
+import com.kbt.amumal.domain.post.dto.CountProjection;
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
 
 import java.util.List;
 
 public interface commentRepository extends JpaRepository<Comment, Integer> {
-    long countByPostIdAndDeletedAtIsNull(int postId);
     List<Comment> findByPostIdAndDeletedAtIsNullOrderByCreatedAtAsc(int postId);
     void deleteByPostId(int postId);
     void deleteByUserId(int userId);
+
+    // N+1 방지: 여러 게시글의 댓글 수를 DTO Projection으로 한 번에 조회
+    @Query("SELECT new com.kbt.amumal.domain.post.dto.CountProjection(c.postId, COUNT(c)) FROM Comment c WHERE c.postId IN :postIds AND c.deletedAt IS NULL GROUP BY c.postId")
+    List<CountProjection> countsByPostIds(@Param("postIds") List<Integer> postIds);
 }
diff --git a/amumal/src/main/java/com/kbt/amumal/domain/post/dto/CountProjection.java b/amumal/src/main/java/com/kbt/amumal/domain/post/dto/CountProjection.java
new file mode 100644
index 0000000..5e98cf1
--- /dev/null
+++ b/amumal/src/main/java/com/kbt/amumal/domain/post/dto/CountProjection.java
@@ -0,0 +1,3 @@
+package com.kbt.amumal.domain.post.dto;
+
+public record CountProjection(Integer postId, Long count) {}
diff --git a/amumal/src/main/java/com/kbt/amumal/domain/post/entity/Post.java b/amumal/src/main/java/com/kbt/amumal/domain/post/entity/Post.java
index 61efd89..6ccf9b7 100644
--- a/amumal/src/main/java/com/kbt/amumal/domain/post/entity/Post.java
+++ b/amumal/src/main/java/com/kbt/amumal/domain/post/entity/Post.java
@@ -25,6 +25,9 @@ public class Post extends BaseEntity {
     @Column(length = 500)
     private String postImageUrl;
 
+    @Column(length = 255)
+    private String postImageOriginalName;
+
     @Column(nullable = false)
     private int userId;
 
@@ -40,15 +43,13 @@ public void updateContent(String content) {
         this.content = content;
     }
 
-    public void updatePostImage(String imageUrl) {
+    public void updatePostImage(String imageUrl, String originalName) {
         this.postImageUrl = imageUrl;
-    }
-
-    public void incrementViewCount() {
-        this.viewCount++;
+        this.postImageOriginalName = originalName;
     }
 
     public void clearPostImage() {
         this.postImageUrl = null;
+        this.postImageOriginalName = null;
     }
 }
\ No newline at end of file
diff --git a/amumal/src/main/java/com/kbt/amumal/domain/post/repository/LikeRepository.java b/amumal/src/main/java/com/kbt/amumal/domain/post/repository/LikeRepository.java
index 7188e31..b5fb54d 100644
--- a/amumal/src/main/java/com/kbt/amumal/domain/post/repository/LikeRepository.java
+++ b/amumal/src/main/java/com/kbt/amumal/domain/post/repository/LikeRepository.java
@@ -1,7 +1,12 @@
 package com.kbt.amumal.domain.post.repository;
 
+import com.kbt.amumal.domain.post.dto.CountProjection;
 import com.kbt.amumal.domain.post.entity.Like;
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
+
+import java.util.List;
 
 public interface LikeRepository extends JpaRepository<Like, Long> {
     boolean existsByUserIdAndPostId(int userId, Integer postId); // 유저+게시글 존재하는지 (좋아요 눌렀는지)
@@ -9,4 +14,8 @@ public interface LikeRepository extends JpaRepository<Like, Long> {
     long countByPostId(Integer postId); // 게시글 좋아요 수
     void deleteByPostId(Integer postId);
     void deleteByUserId(int userId);
+
+    // N+1 방지: 여러 게시글의 좋아요 수를 DTO Projection으로 한 번에 조회
+    @Query("SELECT new com.kbt.amumal.domain.post.dto.CountProjection(l.postId, COUNT(l)) FROM Like l WHERE l.postId IN :postIds GROUP BY l.postId")
+    List<CountProjection> countsByPostIds(@Param("postIds") List<Integer> postIds);
 }
\ No newline at end of file
diff --git a/amumal/src/main/java/com/kbt/amumal/domain/post/service/PostService.java b/amumal/src/main/java/com/kbt/amumal/domain/post/service/PostService.java
index d9a4da3..fd2fbe4 100644
--- a/amumal/src/main/java/com/kbt/amumal/domain/post/service/PostService.java
+++ b/amumal/src/main/java/com/kbt/amumal/domain/post/service/PostService.java
@@ -2,12 +2,14 @@
 
 import com.kbt.amumal.domain.comment.entity.Comment;
 import com.kbt.amumal.domain.comment.repository.commentRepository;
+import com.kbt.amumal.domain.post.dto.CountProjection;
 import com.kbt.amumal.domain.post.dto.PostReqDTO;
 import com.kbt.amumal.domain.post.dto.PostResDTO;
 import com.kbt.amumal.domain.post.entity.Like;
 import com.kbt.amumal.domain.post.entity.Post;
 import com.kbt.amumal.domain.post.repository.LikeRepository;
 import com.kbt.amumal.domain.post.repository.PostRepository;
+import com.kbt.amumal.domain.user.dto.UserProjection;
 import com.kbt.amumal.domain.user.entity.User;
 import com.kbt.amumal.domain.user.repository.UserRepository;
 import com.kbt.amumal.global.common.ImageHandler;
@@ -20,6 +22,7 @@
 import org.springframework.transaction.support.TransactionSynchronizationManager;
 import org.springframework.web.multipart.MultipartFile;
 
+import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 import java.util.stream.Collectors;
@@ -39,10 +42,14 @@ public int create(int id, PostReqDTO.createPost request, MultipartFile postImage
 
         registerImageRollbackOnFailure(postImageUrl);
 
+        String originalName = (postImage != null && !postImage.isEmpty())
+                ? postImage.getOriginalFilename() : null;
+
         Post newPost = postRepository.save(Post.builder()
                 .title(request.title())
                 .content(request.content())
                 .postImageUrl(postImageUrl)
+                .postImageOriginalName(originalName)
                 .userId(id)
                 .build());
 
@@ -76,7 +83,7 @@ public void afterCompletion(int status) {
                 }
             });
 
-            post.updatePostImage(newImageUrl);
+            post.updatePostImage(newImageUrl, postImage.getOriginalFilename());
         }
     }
 
@@ -100,27 +107,28 @@ public PostResDTO.postDetailResponse get(Integer postId) {
         postRepository.incrementViewCount(postId); // clearAutomatically = true → L1 캐시 초기화
         post = postRepository.findById(postId).orElseThrow(); // 증가된 viewCount 반영
 
-        User author = userRepository.findById(post.getUserId()).orElse(null);
         long likeCount = likeRepository.countByPostId(post.getPostId());
 
         List<Comment> comments = commentRepository
                 .findByPostIdAndDeletedAtIsNullOrderByCreatedAtAsc(post.getPostId());
 
-        // 댓글 작성자 ID 목록으로 한 번에 조회 (N+1 방지)
-        List<Integer> commenterIds = comments.stream()
-                .map(Comment::getUserId)
-                .distinct()
-                .collect(Collectors.toList());
-        Map<Integer, User> commenterMap = userRepository.findAllById(commenterIds).stream()
-                .collect(Collectors.toMap(User::getId, u -> u));
+        // 게시글 작성자 + 댓글 작성자 ID를 한 번에 모아 DTO Projection으로 조회 (N+1 방지)
+        List<Integer> userIds = new ArrayList<>();
+        userIds.add(post.getUserId());
+        comments.stream().map(Comment::getUserId).distinct().forEach(userIds::add);
+
+        Map<Integer, UserProjection> userMap = userRepository.findProjectionsByIdIn(userIds).stream()
+                .collect(Collectors.toMap(UserProjection::id, u -> u));
+
+        UserProjection author = userMap.get(post.getUserId());
 
         List<PostResDTO.commentItem> commentItems = comments.stream()
                 .map(comment -> {
-                    User commenter = commenterMap.get(comment.getUserId());
+                    UserProjection commenter = userMap.get(comment.getUserId());
                     return new PostResDTO.commentItem(
                             comment.getCommentId(),
                             comment.getContent(),
-                            commenter != null ? new PostResDTO.userInfo(commenter.getUserId(), commenter.getNickname(), commenter.getProfileImageUrl()) : null,
+                            commenter != null ? new PostResDTO.userInfo(commenter.userId(), commenter.nickname(), commenter.profileImageUrl()) : null,
                             comment.getCreatedAt()
                     );
                 })
@@ -133,7 +141,7 @@ public PostResDTO.postDetailResponse get(Integer postId) {
                 post.getPostImageUrl(),
                 likeCount,
                 post.getViewCount(),
-                author != null ? new PostResDTO.userInfo(author.getUserId(), author.getNickname(), author.getProfileImageUrl()) : null,
+                author != null ? new PostResDTO.userInfo(author.userId(), author.nickname(), author.profileImageUrl()) : null,
                 post.getCreatedAt(),
                 commentItems
         );
@@ -147,18 +155,23 @@ public PostResDTO.postListResponse getList(Integer cursor, int size) {
 
         Integer nextCursor = hasNext ? posts.get(posts.size() - 1).getPostId() : null;
 
-        // 게시글 작성자 ID 목록으로 한 번에 조회 (N+1 방지)
-        List<Integer> authorIds = posts.stream()
-                .map(Post::getUserId)
-                .distinct()
-                .collect(Collectors.toList());
-        Map<Integer, User> authorMap = userRepository.findAllById(authorIds).stream()
-                .collect(Collectors.toMap(User::getId, u -> u));
+        List<Integer> postIds = posts.stream().map(Post::getPostId).collect(Collectors.toList());
+
+        // 작성자 DTO Projection으로 한 번에 조회
+        List<Integer> authorIds = posts.stream().map(Post::getUserId).distinct().collect(Collectors.toList());
+        Map<Integer, UserProjection> authorMap = userRepository.findProjectionsByIdIn(authorIds).stream()
+                .collect(Collectors.toMap(UserProjection::id, u -> u));
+
+        // 카운트 DTO Projection으로 한 번에 조회
+        Map<Integer, Long> likeCounts = likeRepository.countsByPostIds(postIds).stream()
+                .collect(Collectors.toMap(CountProjection::postId, CountProjection::count));
+        Map<Integer, Long> commentCounts = commentRepository.countsByPostIds(postIds).stream()
+                .collect(Collectors.toMap(CountProjection::postId, CountProjection::count));
 
         List<PostResDTO.postListItem> items = posts.stream().map(post -> {
-            User user = authorMap.get(post.getUserId());
-            long likeCount = likeRepository.countByPostId(post.getPostId());
-            long commentCount = commentRepository.countByPostIdAndDeletedAtIsNull(post.getPostId());
+            UserProjection user = authorMap.get(post.getUserId());
+            long likeCount = likeCounts.getOrDefault(post.getPostId(), 0L);
+            long commentCount = commentCounts.getOrDefault(post.getPostId(), 0L);
 
             return new PostResDTO.postListItem(
                     post.getPostId(),
@@ -167,7 +180,7 @@ public PostResDTO.postListResponse getList(Integer cursor, int size) {
                     likeCount,
                     commentCount,
                     post.getViewCount(),
-                    user != null ? new PostResDTO.userInfo(user.getUserId(), user.getNickname(), user.getProfileImageUrl()) : null,
+                    user != null ? new PostResDTO.userInfo(user.userId(), user.nickname(), user.profileImageUrl()) : null,
                     post.getCreatedAt()
             );
         }).collect(Collectors.toList());
diff --git a/amumal/src/main/java/com/kbt/amumal/domain/user/controller/UserController.java b/amumal/src/main/java/com/kbt/amumal/domain/user/controller/UserController.java
index a377f3a..6f19a2c 100644
--- a/amumal/src/main/java/com/kbt/amumal/domain/user/controller/UserController.java
+++ b/amumal/src/main/java/com/kbt/amumal/domain/user/controller/UserController.java
@@ -66,11 +66,11 @@ public ApiResponse<?> updateUserPassword(@LoginUserId int userId, @RequestBody @
         return ApiResponse.success("유저 비밀번호 수정 성공", null);
     }
 
-    @Operation(summary = "프로필 이미지 수정")
+    @Operation(summary = "프로필 이미지 수정", description = "파일을 전송하면 이미지 변경, 파일 없이 요청하면 이미지를 null로 초기화합니다.")
     @PutMapping(value = "/profileImage", consumes = "multipart/form-data")
     public ApiResponse<?> updateUserProfileImage(
             @LoginUserId int userId,
-            @RequestParam MultipartFile profileImage
+            @RequestParam(required = false) MultipartFile profileImage
     ) {
         userService.updateProfileImage(userId, profileImage);
 
diff --git a/amumal/src/main/java/com/kbt/amumal/domain/user/dto/UserProjection.java b/amumal/src/main/java/com/kbt/amumal/domain/user/dto/UserProjection.java
new file mode 100644
index 0000000..dc78c0b
--- /dev/null
+++ b/amumal/src/main/java/com/kbt/amumal/domain/user/dto/UserProjection.java
@@ -0,0 +1,3 @@
+package com.kbt.amumal.domain.user.dto;
+
+public record UserProjection(Integer id, String userId, String nickname, String profileImageUrl) {}
diff --git a/amumal/src/main/java/com/kbt/amumal/domain/user/entity/User.java b/amumal/src/main/java/com/kbt/amumal/domain/user/entity/User.java
index 45706f6..ab2abf2 100644
--- a/amumal/src/main/java/com/kbt/amumal/domain/user/entity/User.java
+++ b/amumal/src/main/java/com/kbt/amumal/domain/user/entity/User.java
@@ -32,6 +32,9 @@ public class User extends BaseEntity {
     @Column(length = 500)
     private String profileImageUrl;
 
+    @Column(length = 255)
+    private String profileImageOriginalName;
+
     @PrePersist
     private void generateUserId() {
         if (userId == null) {
@@ -47,7 +50,8 @@ public void updatePassword(String password) {
         this.password = password;
     }
 
-    public void updateProfileImage(String profileImageUrl) {
+    public void updateProfileImage(String profileImageUrl, String originalName) {
         this.profileImageUrl = profileImageUrl;
+        this.profileImageOriginalName = originalName;
     }
 }
diff --git a/amumal/src/main/java/com/kbt/amumal/domain/user/repository/UserRepository.java b/amumal/src/main/java/com/kbt/amumal/domain/user/repository/UserRepository.java
index 46fe9fc..1e93029 100644
--- a/amumal/src/main/java/com/kbt/amumal/domain/user/repository/UserRepository.java
+++ b/amumal/src/main/java/com/kbt/amumal/domain/user/repository/UserRepository.java
@@ -1,9 +1,10 @@
 package com.kbt.amumal.domain.user.repository;
 
+import com.kbt.amumal.domain.user.dto.UserProjection;
 import com.kbt.amumal.domain.user.entity.User;
-import jakarta.validation.constraints.NotBlank;
-import jakarta.validation.constraints.Size;
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
 
 import java.time.LocalDateTime;
 import java.util.List;
@@ -14,4 +15,8 @@ public interface UserRepository extends JpaRepository<User, Integer> {
     Optional<User> findByNickname(String nickname);
     Optional<User> findByUserId(String userId);
     List<User> findByDeletedAtIsNotNullAndDeletedAtBefore(LocalDateTime cutoff);
+
+    // N+1 방지: 여러 유저 정보를 DTO Projection으로 한 번에 조회
+    @Query("SELECT new com.kbt.amumal.domain.user.dto.UserProjection(u.id, u.userId, u.nickname, u.profileImageUrl) FROM User u WHERE u.id IN :ids")
+    List<UserProjection> findProjectionsByIdIn(@Param("ids") List<Integer> ids);
 }
\ No newline at end of file
diff --git a/amumal/src/main/java/com/kbt/amumal/domain/user/service/UserService.java b/amumal/src/main/java/com/kbt/amumal/domain/user/service/UserService.java
index 229acfd..b6ee66a 100644
--- a/amumal/src/main/java/com/kbt/amumal/domain/user/service/UserService.java
+++ b/amumal/src/main/java/com/kbt/amumal/domain/user/service/UserService.java
@@ -34,11 +34,15 @@ public String create(UserReqDTO.Signup request, MultipartFile profileImage) {
         // 이미지 업로드 성공 후 DB 저장에 실패하면 트랜잭션 롤백 콜백에서 파일 정리
         registerImageRollbackOnFailure(profileImageUrl);
 
+        String originalName = (profileImage != null && !profileImage.isEmpty())
+                ? profileImage.getOriginalFilename() : null;
+
         User newUser = userRepository.save(User.builder()
                 .email(request.email())
                 .password(passwordEncoder.encode(request.password()))
                 .nickname(request.nickname())
                 .profileImageUrl(profileImageUrl)
+                .profileImageOriginalName(originalName)
                 .build());
 
         return newUser.getUserId();
@@ -83,6 +87,23 @@ public void updateProfileImage(int id, MultipartFile profileImage) {
                 .orElseThrow(() -> new CustomException(ErrorCode.USER_NOT_FOUND));
 
         String oldImageUrl = user.getProfileImageUrl();
+
+        // null 또는 빈 파일 → 이미지 초기화
+        if (profileImage == null || profileImage.isEmpty()) {
+            user.updateProfileImage(null, null);
+            if (oldImageUrl != null) {
+                TransactionSynchronizationManager.registerSynchronization(new TransactionSynchronization() {
+                    @Override
+                    public void afterCompletion(int status) {
+                        if (status == TransactionSynchronization.STATUS_COMMITTED) {
+                            fileService.deleteSafely(oldImageUrl);
+                        }
+                    }
+                });
+            }
+            return;
+        }
+
         String newImageUrl = fileService.profileSave(profileImage);
 
         // 커밋 성공 시 기존 이미지 삭제, 롤백 시 새로 업로드한 이미지 삭제
@@ -97,7 +118,7 @@ public void afterCompletion(int status) {
             }
         });
 
-        user.updateProfileImage(newImageUrl);
+        user.updateProfileImage(newImageUrl, profileImage.getOriginalFilename());
     }
 
     private String uploadImageIfPresent(MultipartFile file) {
diff --git a/amumal/src/main/java/com/kbt/amumal/global/common/ImageHandler.java b/amumal/src/main/java/com/kbt/amumal/global/common/ImageHandler.java
index 0854f32..967189b 100644
--- a/amumal/src/main/java/com/kbt/amumal/global/common/ImageHandler.java
+++ b/amumal/src/main/java/com/kbt/amumal/global/common/ImageHandler.java
@@ -2,32 +2,36 @@
 
 import com.kbt.amumal.global.error.CustomException;
 import com.kbt.amumal.global.error.ErrorCode;
+import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.stereotype.Service;
 import org.springframework.web.multipart.MultipartFile;
+import software.amazon.awssdk.core.sync.RequestBody;
+import software.amazon.awssdk.services.s3.S3Client;
+import software.amazon.awssdk.services.s3.model.DeleteObjectRequest;
+import software.amazon.awssdk.services.s3.model.PutObjectRequest;
 
 import java.io.IOException;
 import java.io.InputStream;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.nio.file.Paths;
-import java.nio.file.StandardCopyOption;
 import java.util.Set;
 import java.util.UUID;
 
 /**
- * 이미지 파일 저장/삭제를 담당하는 핸들러.
+ * 이미지 파일 S3 저장/삭제를 담당하는 핸들러.
  *
  * 저장 시 3단계 보안 검증을 순서대로 수행한다.
  *   1. 파일 확장자 검증 (화이트리스트 방식)
  *   2. Content-Type 헤더 검증 (MIME 타입)
  *   3. Magic Bytes 검증 (실제 파일 내용)
  *
- * Content-Type은 클라이언트가 임의로 위조할 수 있으므로 Magic Bytes 검증이 최종 보루가 된다.
+ * 저장 경로:
+ *   - 프로필: {bucket}/backend/profile/{uuid}_{filename}
+ *   - 게시글: {bucket}/backend/post/{uuid}_{filename}
  */
 @Slf4j
 @Service
+@RequiredArgsConstructor
 public class ImageHandler {
 
     /** 허용하는 파일 확장자 목록 (소문자 기준) */
@@ -38,59 +42,31 @@ public class ImageHandler {
             "image/jpg", "image/jpeg", "image/png", "image/gif", "image/webp"
     );
 
-    @Value("${file.upload-dir}")
-    private String uploadDir;
+    private static final String PROFILE_PREFIX = "backend/profile/";
+    private static final String POST_PREFIX = "backend/post/";
 
-    @Value("${file.profile-access-path}")
-    private String profileAccessPath;
+    private final S3Client s3Client;
 
-    @Value("${file.posts-access-path}")
-    private String postsAccessPath;
+    @Value("${aws.s3.bucket}")
+    private String bucket;
+
+    @Value("${aws.region}")
+    private String region;
 
-    /**
-     * 프로필 이미지를 저장하고 접근 URL을 반환한다.
-     *
-     * @param file 업로드된 MultipartFile
-     * @return 저장된 파일의 접근 경로 (예: /profiles/uuid_filename.jpg)
-     * @throws CustomException 디렉토리 미존재, 유효성 검증 실패, IO 오류 시
-     */
     public String profileSave(MultipartFile file) {
-        checkUploadDir();
         validateImage(file);
-        String filename = UUID.randomUUID() + "_" + file.getOriginalFilename();
-        Path imageFilePath = Paths.get(uploadDir, filename);
-        try {
-            Files.copy(file.getInputStream(), imageFilePath, StandardCopyOption.REPLACE_EXISTING);
-        } catch (IOException e) {
-            log.error("프로필 이미지 저장 실패: {}", filename, e);
-            throw new CustomException(ErrorCode.IMAGE_UPLOAD_FAILED);
-        }
-        return profileAccessPath + "/" + filename;
+        String key = PROFILE_PREFIX + UUID.randomUUID() + extractExtension(file.getOriginalFilename());
+        return upload(file, key);
     }
 
-    /**
-     * 게시글 이미지를 저장하고 접근 URL을 반환한다.
-     *
-     * @param file 업로드된 MultipartFile
-     * @return 저장된 파일의 접근 경로 (예: /profiles/uuid_filename.jpg)
-     * @throws CustomException 디렉토리 미존재, 유효성 검증 실패, IO 오류 시
-     */
     public String postSave(MultipartFile file) {
-        checkUploadDir();
         validateImage(file);
-        String filename = UUID.randomUUID() + "_" + file.getOriginalFilename();
-        Path imageFilePath = Paths.get(uploadDir, filename);
-        try {
-            Files.copy(file.getInputStream(), imageFilePath, StandardCopyOption.REPLACE_EXISTING);
-        } catch (IOException e) {
-            log.error("게시글 이미지 저장 실패: {}", filename, e);
-            throw new CustomException(ErrorCode.IMAGE_UPLOAD_FAILED);
-        }
-        return postsAccessPath + "/" + filename;
+        String key = POST_PREFIX + UUID.randomUUID() + extractExtension(file.getOriginalFilename());
+        return upload(file, key);
     }
 
     /**
-     * 이미지 URL에 해당하는 파일을 디스크에서 삭제한다.
+     * S3에서 이미지를 삭제한다.
      * URL이 null이거나 빈 값이면 아무 작업도 하지 않는다.
      * 삭제 실패 시 예외를 던지지 않고 경고 로그만 남긴다.
      * 트랜잭션 콜백 등 실패해도 롤백할 수 없는 컨텍스트에서 사용한다.
@@ -99,26 +75,46 @@ public String postSave(MultipartFile file) {
      */
     public void deleteSafely(String imageUrl) {
         if (imageUrl == null || imageUrl.isBlank()) return;
-        String filename = Paths.get(imageUrl).getFileName().toString();
-        Path filePath = Paths.get(uploadDir, filename);
         try {
-            Files.deleteIfExists(filePath);
-        } catch (IOException e) {
-            log.warn("이미지 삭제 실패 (고아 파일 가능성): {}", filePath, e);
+            String key = extractKey(imageUrl);
+            s3Client.deleteObject(DeleteObjectRequest.builder()
+                    .bucket(bucket)
+                    .key(key)
+                    .build());
+        } catch (Exception e) {
+            log.warn("S3 이미지 삭제 실패 (고아 파일 가능성): {}", imageUrl, e);
         }
     }
 
-    /**
-     * 업로드 디렉토리가 실제로 존재하는지 확인한다.
-     * 서버 설정 오류나 마운트 해제 등의 상황을 저장 전에 조기 감지하기 위해 매 저장마다 호출한다.
-     */
-    private void checkUploadDir() {
-        Path dirPath = Paths.get(uploadDir);
-        if (!Files.exists(dirPath) || !Files.isDirectory(dirPath)) {
-            throw new CustomException(ErrorCode.UPLOAD_DIR_NOT_FOUND);
+    private String upload(MultipartFile file, String key) {
+        try {
+            PutObjectRequest request = PutObjectRequest.builder()
+                    .bucket(bucket)
+                    .key(key)
+                    .contentType(file.getContentType())
+                    .contentLength(file.getSize())
+                    .build();
+            s3Client.putObject(request, RequestBody.fromBytes(file.getBytes()));
+            return "https://" + bucket + ".s3." + region + ".amazonaws.com/" + key;
+        } catch (IOException e) {
+            log.error("S3 이미지 업로드 실패: {}", key, e);
+            throw new CustomException(ErrorCode.IMAGE_UPLOAD_FAILED);
         }
     }
 
+    /** 파일명에서 `.ext` 형식의 확장자를 반환한다. 확장자 없으면 빈 문자열. */
+    private String extractExtension(String originalFilename) {
+        if (originalFilename == null || !originalFilename.contains(".")) return "";
+        return "." + originalFilename.substring(originalFilename.lastIndexOf('.') + 1).toLowerCase();
+    }
+
+    /** URL에서 S3 객체 키를 추출한다 (`.amazonaws.com/` 이후 부분). */
+    private String extractKey(String imageUrl) {
+        int idx = imageUrl.indexOf(".amazonaws.com/");
+        if (idx == -1) return imageUrl;
+        return imageUrl.substring(idx + ".amazonaws.com/".length());
+    }
+
     /**
      * 확장자 → Content-Type → Magic Bytes 순서로 이미지 유효성을 검증한다.
      * 앞 단계에서 실패하면 이후 단계는 실행되지 않는다.
diff --git a/amumal/src/main/java/com/kbt/amumal/global/config/S3Config.java b/amumal/src/main/java/com/kbt/amumal/global/config/S3Config.java
new file mode 100644
index 0000000..200ea26
--- /dev/null
+++ b/amumal/src/main/java/com/kbt/amumal/global/config/S3Config.java
@@ -0,0 +1,31 @@
+package com.kbt.amumal.global.config;
+
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import software.amazon.awssdk.auth.credentials.AwsBasicCredentials;
+import software.amazon.awssdk.auth.credentials.StaticCredentialsProvider;
+import software.amazon.awssdk.regions.Region;
+import software.amazon.awssdk.services.s3.S3Client;
+
+@Configuration
+public class S3Config {
+
+    @Value("${aws.credentials.access-key}")
+    private String accessKey;
+
+    @Value("${aws.credentials.secret-key}")
+    private String secretKey;
+
+    @Value("${aws.region}")
+    private String region;
+
+    @Bean
+    public S3Client s3Client() {
+        return S3Client.builder()
+                .region(Region.of(region))
+                .credentialsProvider(StaticCredentialsProvider.create(
+                        AwsBasicCredentials.create(accessKey, secretKey)))
+                .build();
+    }
+}
diff --git a/amumal/src/main/java/com/kbt/amumal/global/config/WebConfig.java b/amumal/src/main/java/com/kbt/amumal/global/config/WebConfig.java
index cf4a979..46c41fd 100644
--- a/amumal/src/main/java/com/kbt/amumal/global/config/WebConfig.java
+++ b/amumal/src/main/java/com/kbt/amumal/global/config/WebConfig.java
@@ -3,12 +3,10 @@
 import com.kbt.amumal.global.interceptor.AuthInterceptor;
 import com.kbt.amumal.global.interceptor.LoginUserArgumentResolver;
 import lombok.RequiredArgsConstructor;
-import org.springframework.beans.factory.annotation.Value;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.web.method.support.HandlerMethodArgumentResolver;
 import org.springframework.web.servlet.config.annotation.CorsRegistry;
 import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
-import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
 import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
 
 import java.util.List;
@@ -17,15 +15,6 @@
 @RequiredArgsConstructor
 public class WebConfig implements WebMvcConfigurer {
 
-    @Value("${file.upload-dir}")
-    private String uploadDir;
-
-    @Value("${file.profile-access-path}")
-    private String profileAccessPath;
-
-    @Value("${file.posts-access-path}")
-    private String postsAccessPath;
-
     private final AuthInterceptor authInterceptor;
     private final LoginUserArgumentResolver loginUserArgumentResolver;
 
@@ -40,20 +29,8 @@ public void addCorsMappings(CorsRegistry registry) {
                         "http://localhost:8080"
                 )
                 .allowedMethods("GET", "POST", "PUT", "PATCH", "DELETE", "OPTIONS")
-                .allowedHeaders("Content-Type", "Authorization");
-    }
-
-    // 정적 리소스 경로 매핑: env의 접근 경로 요청을 실제 업로드 디렉토리로 연결
-    @Override
-    public void addResourceHandlers(ResourceHandlerRegistry registry) {
-        String location = "file:" + uploadDir + (uploadDir.endsWith("/") ? "" : "/");
-        registry.addResourceHandler(profileAccessPath + "/**").addResourceLocations(location);
-        // /post-images/** 는 API 컨트롤러(/posts/**)와 충돌하지 않는 전용 정적 이미지 경로
-        registry.addResourceHandler("/post-images/**").addResourceLocations(location);
-        if (!postsAccessPath.equals(profileAccessPath) && !postsAccessPath.equals("/post-images")) {
-            // 기존 /posts/** 경로로 저장된 이미지도 계속 서빙 (하위 호환)
-            registry.addResourceHandler(postsAccessPath + "/**").addResourceLocations(location);
-        }
+                .allowedHeaders("Content-Type", "Authorization")
+                .allowCredentials(true); // 쿠키 포함 요청 허용 (SameSite=None Secure 쿠키와 함께 사용)
     }
 
     // 인터셉터 - 모든 요청에 AuthInterceptor 적용 (@LoginUserId 없는 경로는 적용 안됨)
diff --git a/amumal/src/main/java/com/kbt/amumal/global/error/ErrorCode.java b/amumal/src/main/java/com/kbt/amumal/global/error/ErrorCode.java
index 63aa72a..10694dd 100644
--- a/amumal/src/main/java/com/kbt/amumal/global/error/ErrorCode.java
+++ b/amumal/src/main/java/com/kbt/amumal/global/error/ErrorCode.java
@@ -47,7 +47,6 @@ public enum ErrorCode {
     // 이미지
     INVALID_IMAGE_EXTENSION(HttpStatus.BAD_REQUEST, "유효하지 않은 요청입니다.", "허용되지 않는 이미지 확장자입니다. (jpg, jpeg, png, gif, webp)"),
     INVALID_IMAGE_MIME_TYPE(HttpStatus.BAD_REQUEST, "유효하지 않은 요청입니다.", "유효하지 않은 이미지 파일입니다."),
-    UPLOAD_DIR_NOT_FOUND(HttpStatus.INTERNAL_SERVER_ERROR, "서버 에러", "업로드 디렉토리를 찾을 수 없습니다."),
     IMAGE_UPLOAD_FAILED(HttpStatus.INTERNAL_SERVER_ERROR, "서버 에러", "이미지 업로드에 실패했습니다.");
 
     private final HttpStatus status;
diff --git a/amumal/src/main/java/com/kbt/amumal/global/interceptor/LoginUserArgumentResolver.java b/amumal/src/main/java/com/kbt/amumal/global/interceptor/LoginUserArgumentResolver.java
index 5371a09..343ba7e 100644
--- a/amumal/src/main/java/com/kbt/amumal/global/interceptor/LoginUserArgumentResolver.java
+++ b/amumal/src/main/java/com/kbt/amumal/global/interceptor/LoginUserArgumentResolver.java
@@ -11,7 +11,6 @@
 @Component
 public class LoginUserArgumentResolver implements HandlerMethodArgumentResolver {
 
-    // @LoginUserId 어노테이션이 붙은 파라미터일 때만 이 Resolver가 동작하도록 true 반환
     @Override
     public boolean supportsParameter(MethodParameter parameter) {
         return parameter.hasParameterAnnotation(LoginUserId.class);
@@ -21,6 +20,11 @@ public boolean supportsParameter(MethodParameter parameter) {
     @Override
     public Object resolveArgument(MethodParameter parameter, ModelAndViewContainer mavContainer,
                                   NativeWebRequest webRequest, WebDataBinderFactory binderFactory) {
+        Class<?> type = parameter.getParameterType();
+        if (type != int.class && type != Integer.class) {
+            throw new IllegalStateException("@LoginUserId는 int 또는 Integer 타입에만 사용할 수 있습니다.");
+        }
+
         HttpServletRequest request = (HttpServletRequest) webRequest.getNativeRequest();
         return request.getAttribute("userId"); // @LoginUserId 파라미터에 자동으로 주입
     }
diff --git a/amumal/src/main/java/com/kbt/amumal/global/util/JwtUtil.java b/amumal/src/main/java/com/kbt/amumal/global/util/JwtUtil.java
index b387b6f..6d2d140 100644
--- a/amumal/src/main/java/com/kbt/amumal/global/util/JwtUtil.java
+++ b/amumal/src/main/java/com/kbt/amumal/global/util/JwtUtil.java
@@ -8,6 +8,7 @@
 import org.springframework.stereotype.Component;
 
 import java.security.Key;
+import java.time.Duration;
 import java.time.ZonedDateTime;
 import java.util.Date;
 
@@ -16,15 +17,18 @@
 public class JwtUtil {
 
     private final Key key; // 서명에 사용할 HMAC 키
-    private final long accessTokenExpTime; // 액세스 토큰 만료 시간 (초)
+    private final long accessTokenExpTime;   // 액세스 토큰 만료 시간 (초)
+    private final long refreshTokenExpTime;  // 리프레시 토큰 만료 시간 (초)
 
     public JwtUtil(
             @Value("${jwt.secret}") String secretKey,
-            @Value("${jwt.expiration_time}") long accessTokenExpTime
+            @Value("${jwt.expiration_time}") long accessTokenExpTime,
+            @Value("${jwt.refresh_expiration_time}") long refreshTokenExpTime
     ) {
         byte[] keyBytes = Decoders.BASE64.decode(secretKey); // Base64 디코딩
         this.key = Keys.hmacShaKeyFor(keyBytes); // HMAC-SHA 키 생성
         this.accessTokenExpTime = accessTokenExpTime;
+        this.refreshTokenExpTime = refreshTokenExpTime;
     }
 
     // 액세스 토큰 생성
@@ -32,10 +36,15 @@ public String createAccessToken(int id, String email) {
         return createToken(id, email, accessTokenExpTime);
     }
 
+    // 리프레시 토큰 생성
+    public String createRefreshToken(int id, String email) {
+        return createToken(id, email, refreshTokenExpTime);
+    }
+
     // JWT 생성
-    private String createToken(int id, String email, long expireTime) {
+    private String createToken(int id, String email, long expireTimeMs) {
         ZonedDateTime now = ZonedDateTime.now();
-        ZonedDateTime tokenValidity = now.plusSeconds(expireTime);
+        ZonedDateTime tokenValidity = now.plus(Duration.ofMillis(expireTimeMs));
 
         return Jwts.builder()
                 .claim("id", id)
@@ -51,7 +60,11 @@ public int getId(String token) {
         return parseClaims(token).get("id", Integer.class);
     }
 
-    // JWT 유효성 검증
+    // 토큰에서 email 추출
+    public String getEmail(String token) {
+        return parseClaims(token).get("email", String.class);
+    }
+
     public boolean validateToken(String token) {
         try {
             Jwts.parserBuilder().setSigningKey(key).build().parseClaimsJws(token);
@@ -71,9 +84,9 @@ public boolean validateToken(String token) {
     }
 
     // JWT 페이로드 추출
-    public Claims parseClaims(String accessToken) {
+    public Claims parseClaims(String token) {
         try {
-            return Jwts.parserBuilder().setSigningKey(key).build().parseClaimsJws(accessToken).getBody();
+            return Jwts.parserBuilder().setSigningKey(key).build().parseClaimsJws(token).getBody();
         } catch (ExpiredJwtException e) {
             return e.getClaims(); // 만료된 토큰도 claims 반환 (토큰 재발급 시 userId 필요)
         }
diff --git a/amumal/src/main/resources/application.properties b/amumal/src/main/resources/application.properties
index 7b31717..b9b8044 100644
--- a/amumal/src/main/resources/application.properties
+++ b/amumal/src/main/resources/application.properties
@@ -1,23 +1,55 @@
 spring.application.name=amumal
 
-spring.datasource.url=jdbc:mysql://${DB_HOST}:3306/${DB_NAME}?allowPublicKeyRetrieval=true&useSSL=false&serverTimezone=UTC&characterEncoding=UTF-8
+spring.datasource.url=jdbc:mysql://${DB_HOST}:3306/${DB_NAME}?allowPublicKeyRetrieval=true&useSSL=false&serverTimezone=Asia/Seoul&characterEncoding=UTF-8
 spring.datasource.username=${DB_USERNAME}
 spring.datasource.password=${DB_PASSWORD}
 spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
 
-spring.jpa.hibernate.ddl-auto=update
+spring.jpa.hibernate.ddl-auto=${DDL_AUTO_SET}
 spring.jpa.show-sql=true
 spring.jpa.database-platform=org.hibernate.dialect.MySQLDialect
-
-file.upload-dir=${UPLOAD_DIR}
-file.profile-access-path=${PROFILE_FILE_ACCESS_PATH}
-file.posts-access-path=${POSTS_FILE_ACCESS_PATH}
+spring.jpa.properties.hibernate.jdbc.time_zone=Asia/Seoul
 
 spring.servlet.multipart.max-file-size=${MAX_FILE_SIZE}
 spring.servlet.multipart.max-request-size=${MAX_REQUEST_SIZE}
 
-jwt.expiration_time=86400000
+# AWS S3
+aws.credentials.access-key=${AWS_ACCESS_KEY}
+aws.credentials.secret-key=${AWS_SECRET_KEY}
+aws.region=${AWS_REGION}
+aws.s3.bucket=${AWS_S3_BUCKET}
+
+# Access Token: 1시간(ms), Refresh Token: 30일(ms)
+jwt.expiration_time=3600000
+jwt.refresh_expiration_time=2592000000
 jwt.secret=${JWT_SECRET}
 
+server.forward-headers-strategy=framework
+
+# Redis
+spring.data.redis.host=${REDIS_HOST:localhost}
+spring.data.redis.port=${REDIS_PORT:6379}
+spring.data.redis.password=${REDIS_PASSWORD:}
+
+# JSON 직렬화 타임존
+spring.jackson.time-zone=Asia/Seoul
+
 springdoc.enable-data-rest=false
-server.url=${SERVER_URL:http://localhost:8080}
\ No newline at end of file
+server.url=${SERVER_URL}
+
+# 로그 파일 이름 설정
+logging.file.name=/home/ubuntu/KBT/amumal/logs/app.log
+
+# 로그 레벨 설정
+logging.level.root=INFO
+logging.level.com.kbt.amumal=DEBUG
+
+# 하루 단위로 로그를 쪼개기 -> 최대 7일치만 보관, 나머지 삭제
+logging.logback.rollingpolicy.max-history=7
+
+# 파일 한 개당 최대 10MB까지만 커지게 제한 (넘으면 .gz 압축)
+logging.logback.rollingpolicy.max-file-size=10MB
+
+# 패턴 설정
+logging.pattern.console=%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n
+logging.pattern.file=%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n
\ No newline at end of file