diff --git a/build.gradle b/build.gradle
index 610d6a6..033c4ee 100644
--- a/build.gradle
+++ b/build.gradle
@@ -19,7 +19,16 @@ repositories {
 }
 
 dependencies {
+    // 기본 웹 라이브러리
 	implementation 'org.springframework.boot:spring-boot-starter-web'
+    // 데이터베이스 연동(JPA) 라이브러리
+    implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
+    // 테스트용 H2 인메모리 데이터베이스
+    runtimeOnly 'com.h2database:h2'
+    // Lombok 라이브러리 (코드 자동 생성)
+    compileOnly 'org.projectlombok:lombok'
+    annotationProcessor 'org.projectlombok:lombok'
+    // 기본 테스트 라이브러리
 	testImplementation 'org.springframework.boot:spring-boot-starter-test'
 	testRuntimeOnly 'org.junit.platform:junit-platform-launcher'
 }
diff --git a/data/devsns_db.mv.db b/data/devsns_db.mv.db
new file mode 100644
index 0000000..9220cb8
Binary files /dev/null and b/data/devsns_db.mv.db differ
diff --git a/src/main/java/com/example/devSns/controller/CommentController.java b/src/main/java/com/example/devSns/controller/CommentController.java
new file mode 100644
index 0000000..06f2062
--- /dev/null
+++ b/src/main/java/com/example/devSns/controller/CommentController.java
@@ -0,0 +1,39 @@
+package com.example.devSns.controller;
+
+import com.example.devSns.entity.Comment;
+import com.example.devSns.service.CommentService;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.List;
+
+@RestController
+@RequestMapping("/posts/{postId}/comments")
+public class CommentController {
+
+    private final CommentService commentService;
+
+    public CommentController(CommentService commentService) {
+        this.commentService = commentService;
+    }
+
+    @PostMapping
+    public Comment createComment(@PathVariable Long postId, @RequestBody Comment comment) {
+        return commentService.createComment(postId, comment);
+    }
+
+    @GetMapping
+    public List<Comment> getCommentsByPostId(@PathVariable Long postId) {
+        return commentService.getCommentsByPostId(postId);
+    }
+
+    @PutMapping("/{id}")
+    public Comment updateComment(@PathVariable Long id, @RequestBody Comment comment) {
+        return commentService.updateComment(id, comment);
+    }
+
+    @DeleteMapping("/{id}")
+    public void deleteComment(@PathVariable Long id) {
+        commentService.deleteComment(id);
+    }
+}
+
diff --git a/src/main/java/com/example/devSns/controller/PostController.java b/src/main/java/com/example/devSns/controller/PostController.java
new file mode 100644
index 0000000..b9d8030
--- /dev/null
+++ b/src/main/java/com/example/devSns/controller/PostController.java
@@ -0,0 +1,51 @@
+package com.example.devSns.controller;
+
+import com.example.devSns.entity.Post;
+import com.example.devSns.service.PostService;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.List;
+
+@RestController
+@RequestMapping("/posts")
+public class PostController {
+    private final PostService postService;
+
+    public PostController(PostService postService) {
+        this.postService = postService;
+    }
+
+    @PostMapping
+    public ResponseEntity<Post> createPost(@RequestBody Post post) {
+        Post createdPost = postService.createPost(post);
+        return ResponseEntity.status(HttpStatus.CREATED).body(createdPost);
+    }
+
+    @GetMapping
+    public ResponseEntity<List<Post>> getAllPosts() {
+        List<Post> posts = postService.getAllPosts();
+        return ResponseEntity.ok(posts);
+    }
+
+    @GetMapping("/{id}")
+    public ResponseEntity<Post> getPostById(@PathVariable Long id) {
+        Post post = postService.getPostById(id);
+        return ResponseEntity.ok(post);
+    }
+
+    @PutMapping("/{id}")
+    public ResponseEntity<Post> updatePost(
+            @PathVariable Long id,
+            @RequestBody Post updatedPost) {
+        Post post = postService.updatePost(id, updatedPost);
+        return ResponseEntity.ok(post);
+    }
+
+    @DeleteMapping("/{id}")
+    public ResponseEntity<Void> deletePost(@PathVariable Long id) {
+        postService.deletePost(id);
+        return ResponseEntity.noContent().build();
+    }
+}
diff --git a/src/main/java/com/example/devSns/entity/Comment.java b/src/main/java/com/example/devSns/entity/Comment.java
new file mode 100644
index 0000000..f07b3be
--- /dev/null
+++ b/src/main/java/com/example/devSns/entity/Comment.java
@@ -0,0 +1,43 @@
+package com.example.devSns.entity;
+
+import jakarta.persistence.*;
+import lombok.*;
+import java.time.LocalDateTime;
+
+@Entity
+@Table(name = "comments")
+@Getter
+@Setter
+@NoArgsConstructor
+@AllArgsConstructor
+@Builder
+public class Comment {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY) // auto-incremented
+    private Long id;
+
+    @Column(nullable = false)
+    private String content;
+
+    @Column(nullable = false)
+    private String writer;
+
+    @ManyToOne(fetch = FetchType.LAZY) // 댓글 조회 시 Post는 필요할 때만 불러옴
+    @JoinColumn(name = "post_id", nullable = false)
+    private Post post;
+
+    @Column(nullable = false, updatable = false)
+    private LocalDateTime createdAt;
+
+    private LocalDateTime updatedAt;
+
+    @PrePersist
+    public void prePersist() {
+        createdAt = LocalDateTime.now();
+    }
+
+    @PreUpdate
+    public void preUpdate() {
+        updatedAt = LocalDateTime.now();
+    }
+}
diff --git a/src/main/java/com/example/devSns/entity/Post.java b/src/main/java/com/example/devSns/entity/Post.java
new file mode 100644
index 0000000..bd058ca
--- /dev/null
+++ b/src/main/java/com/example/devSns/entity/Post.java
@@ -0,0 +1,49 @@
+package com.example.devSns.entity;
+
+import jakarta.persistence.*;
+import lombok.*;
+import java.time.LocalDateTime;
+import java.util.ArrayList;
+import java.util.List;
+
+@Entity
+@Table(name = "posts")
+@Getter
+@Setter
+@NoArgsConstructor
+@AllArgsConstructor
+@Builder
+public class Post {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @Column(nullable = false)
+    private String title;
+
+    @Column(nullable = false, length = 1000)
+    private String content;
+
+    @Column(nullable = false)
+    private String writer;
+
+    private int likeCount = 0;
+
+    @Column(nullable = false, updatable = false)
+    private LocalDateTime createdAt;
+
+    private LocalDateTime updatedAt;
+
+    @OneToMany(mappedBy = "post", cascade = CascadeType.ALL, orphanRemoval = true)
+    private List<Comment> comments = new ArrayList<>();
+
+    @PrePersist
+    public void prePersist() {
+        createdAt = LocalDateTime.now();
+    }
+
+    @PreUpdate
+    public void preUpdate() {
+        updatedAt = LocalDateTime.now();
+    }
+}
diff --git a/src/main/java/com/example/devSns/repository/CommentRepository.java b/src/main/java/com/example/devSns/repository/CommentRepository.java
new file mode 100644
index 0000000..22271d9
--- /dev/null
+++ b/src/main/java/com/example/devSns/repository/CommentRepository.java
@@ -0,0 +1,12 @@
+package com.example.devSns.repository;
+
+import com.example.devSns.entity.Comment;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+import java.util.List;
+
+@Repository
+public interface CommentRepository extends JpaRepository<Comment, Long> {
+    // Comment에서 연관된 Post 객체의 id 기준
+    List<Comment> findByPost_Id(Long postId);
+}
diff --git a/src/main/java/com/example/devSns/repository/PostRepository.java b/src/main/java/com/example/devSns/repository/PostRepository.java
new file mode 100644
index 0000000..a648eaf
--- /dev/null
+++ b/src/main/java/com/example/devSns/repository/PostRepository.java
@@ -0,0 +1,10 @@
+package com.example.devSns.repository;
+
+import com.example.devSns.entity.Post;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface PostRepository extends JpaRepository<Post, Long> {
+
+}
diff --git a/src/main/java/com/example/devSns/service/CommentService.java b/src/main/java/com/example/devSns/service/CommentService.java
new file mode 100644
index 0000000..d5be05d
--- /dev/null
+++ b/src/main/java/com/example/devSns/service/CommentService.java
@@ -0,0 +1,55 @@
+package com.example.devSns.service;
+
+import com.example.devSns.entity.Comment;
+import com.example.devSns.entity.Post;
+import com.example.devSns.repository.CommentRepository;
+import com.example.devSns.repository.PostRepository;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.List;
+
+@Service
+@Transactional
+public class CommentService {
+
+    private final CommentRepository commentRepository;
+    private final PostRepository postRepository;
+
+    public CommentService(CommentRepository commentRepository,
+                          PostRepository postRepository) {
+        this.commentRepository = commentRepository;
+        this.postRepository = postRepository;
+    }
+
+    public Comment createComment(Long postId, Comment comment) {
+        Post post = postRepository.findById(postId)
+                .orElseThrow(() -> new RuntimeException("Post not found with id: " + postId));
+        comment.setPost(post);
+        return commentRepository.save(comment);
+    }
+
+    @Transactional(readOnly = true)
+    public List<Comment> getCommentsByPostId(Long postId) {
+        return commentRepository.findByPost_Id(postId);
+    }
+
+    public Comment updateComment(Long id, Comment updatedComment) {
+        Comment foundComment = commentRepository.findById(id)
+                .orElseThrow(() -> new RuntimeException("Comment not found with id: " + id));
+
+        foundComment.setContent(updatedComment.getContent());
+        foundComment.setWriter(updatedComment.getWriter());
+
+        return commentRepository.save(foundComment);
+    }
+
+    public void deleteComment(Long id) {
+        if (!commentRepository.existsById(id)) {
+            throw new RuntimeException("Comment not found with id: " + id);
+        }
+        commentRepository.deleteById(id);
+    }
+}
+
+
diff --git a/src/main/java/com/example/devSns/service/PostService.java b/src/main/java/com/example/devSns/service/PostService.java
new file mode 100644
index 0000000..0d1297e
--- /dev/null
+++ b/src/main/java/com/example/devSns/service/PostService.java
@@ -0,0 +1,52 @@
+package com.example.devSns.service;
+
+import com.example.devSns.entity.Post;
+import com.example.devSns.repository.PostRepository;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.List;
+
+@Service
+@Transactional
+public class PostService {
+    private final PostRepository postRepository;
+
+    public PostService(PostRepository postRepository) {
+        this.postRepository = postRepository;
+    }
+
+    public Post createPost(Post post) {
+        return postRepository.save(post);
+    }
+
+    @Transactional(readOnly = true)
+    public List<Post> getAllPosts() {
+        return postRepository.findAll();
+    }
+
+    @Transactional(readOnly = true)
+    public Post getPostById(Long id) {
+        return postRepository.findById(id)
+                .orElseThrow(() -> new RuntimeException("Post not found with id: " + id));
+    }
+
+    public Post updatePost(Long id, Post updatedPost) {
+        Post foundPost = postRepository.findById(id)
+                .orElseThrow(() -> new RuntimeException("Post not found with id: " + id));
+
+        foundPost.setTitle(updatedPost.getTitle());
+        foundPost.setContent(updatedPost.getContent());
+        foundPost.setWriter(updatedPost.getWriter());
+
+        return postRepository.save(foundPost);
+    }
+
+    public void deletePost(Long id) {
+        if (!postRepository.existsById(id)) {
+            throw new RuntimeException("Post not found with id: " + id);
+        }
+        postRepository.deleteById(id);
+    }
+}
+