diff --git a/app/mypage/_components/ScreenMyPage.tsx b/app/mypage/_components/ScreenMyPage.tsx
index b65aff2..2887f65 100644
--- a/app/mypage/_components/ScreenMyPage.tsx
+++ b/app/mypage/_components/ScreenMyPage.tsx
@@ -1,7 +1,8 @@
 "use client";
 
-import React, { useState, useEffect, useMemo } from "react";
+import React, { useState, useEffect, useMemo, useTransition } from "react";
 import { BackButton } from "@/components/ui/BackButton";
+import { useRouter } from "next/navigation";
 import Button from "@/components/ui/Button";
 import ProfileButton from "@/app/profile-builder/_components/ProfileButton";
 import ProfileImageSelection from "@/app/profile-image/_components/ProfileImageSelection";
@@ -39,6 +40,7 @@ import {
   NicknameAvailabilityResponse,
 } from "@/hooks/useNicknameAvailability";
 import axios from "axios";
+import { withdrawAction } from "@/lib/actions/authAction";
 
 /* ───── 상수 맵핑 ───── */
 
@@ -162,6 +164,7 @@ interface ScreenMyPageProps {
 }
 
 const ScreenMyPage = ({ initialProfile }: ScreenMyPageProps) => {
+  const router = useRouter();
   // 서버에서 프로필 데이터 가져오기
   const { data: profileResponse, isLoading, isError } = useMyProfile();
   const { mutate: updateMyProfileMutate, isPending: isUpdating } =
@@ -171,7 +174,8 @@ const ScreenMyPage = ({ initialProfile }: ScreenMyPageProps) => {
     isPending: isCheckingNickname,
   } = useNicknameAvailability();
 
-  const isSubmitting = isUpdating || isCheckingNickname;
+  const [isWithdrawing, startWithdrawTransition] = useTransition();
+  const isSubmitting = isUpdating || isCheckingNickname || isWithdrawing;
 
   const profile = profileResponse?.data;
 
@@ -860,10 +864,23 @@ const ScreenMyPage = ({ initialProfile }: ScreenMyPageProps) => {
         {/* ── 탈퇴하기 ── */}
         <button
           type="button"
-          className="typo-16-500 self-center text-[#B3B3B3] underline"
+          className="typo-16-500 self-center text-[#B3B3B3] underline disabled:opacity-50"
+          disabled={isSubmitting}
           onClick={() => {
-            if (confirm("정말 탈퇴하시겠습니까?")) {
-              // TODO: 탈퇴 API 호출
+            if (
+              confirm(
+                "정말 탈퇴하시겠습니까?\n모든 데이터가 삭제되며 복구할 수 없습니다.",
+              )
+            ) {
+              startWithdrawTransition(async () => {
+                const result = await withdrawAction();
+                if (result.success) {
+                  alert(result.message);
+                  router.replace("/");
+                } else {
+                  alert(result.message);
+                }
+              });
             }
           }}
         >
diff --git a/lib/actions/admin/adminLoginAction.ts b/lib/actions/admin/adminLoginAction.ts
index 0dd0ee0..30f3ccf 100644
--- a/lib/actions/admin/adminLoginAction.ts
+++ b/lib/actions/admin/adminLoginAction.ts
@@ -32,54 +32,8 @@ export async function adminLoginAction(
       body: { email, password },
     });
 
-    // 🍪 백엔드로부터 받은 쿠키가 있다면 브라우저에 배달해줍니다.
-    if (setCookie) {
-      const { cookies } = await import("next/headers");
-      const cookieStore = await cookies();
-
-      setCookie.forEach((cookieStr) => {
-        const [nameValue, ...options] = cookieStr.split(";");
-        const [name, ...nameParts] = nameValue.split("=");
-        const value = nameParts.join("=");
-
-        const cookieOptions: {
-          path?: string;
-          httpOnly?: boolean;
-          secure?: boolean;
-          maxAge?: number;
-          expires?: Date;
-          sameSite?: "strict" | "lax" | "none" | boolean;
-          domain?: string;
-        } = {};
-
-        options.forEach((opt) => {
-          const [key, ...valueParts] = opt.trim().split("=");
-          const val = valueParts.join("=");
-          const k = key.toLowerCase();
-          if (k === "path") cookieOptions.path = val;
-          if (k === "httponly") cookieOptions.httpOnly = true;
-          if (k === "secure") cookieOptions.secure = true;
-          if (k === "max-age") cookieOptions.maxAge = parseInt(val);
-          if (k === "expires") cookieOptions.expires = new Date(val);
-          if (k === "domain") cookieOptions.domain = val;
-          if (k === "samesite")
-            cookieOptions.sameSite = val.toLowerCase() as
-              | "strict"
-              | "lax"
-              | "none";
-        });
-
-        // 배포 환경에서는 백엔드와 직접 통신하므로, 서브도메인 간 공유를 위해 명시적으로 도메인 설정
-        if (process.env.NODE_ENV === "production") {
-          cookieOptions.domain = ".comatching.site";
-        } else {
-          // 로컬에서는 도메인을 지워야 브라우저가 localhost에서 쿠키를 정상적으로 저장함
-          delete cookieOptions.domain;
-        }
-
-        cookieStore.set(name, value, cookieOptions);
-      });
-    }
+    // 🍪 serverApi.post 내부에서 response header의 set-cookie를 파싱하여
+    // 이미 cookieStore에 저장했으므로, 여기서 별도로 처리할 필요가 없습니다.
   } catch (error) {
     if (
       error instanceof Error &&
diff --git a/lib/actions/authAction.ts b/lib/actions/authAction.ts
index 2923fd2..01a69fe 100644
--- a/lib/actions/authAction.ts
+++ b/lib/actions/authAction.ts
@@ -55,3 +55,48 @@ export async function resetPasswordAction(
     };
   }
 }
+
+export type WithdrawResponse = {
+  success: boolean;
+  message: string;
+};
+
+/**
+ * 회원 탈퇴 Server Action
+ */
+export async function withdrawAction(): Promise<WithdrawResponse> {
+  try {
+    await serverApi.delete({
+      path: "/api/auth/withdraw",
+    });
+
+    // 탈퇴 성공 시 로컬 쿠키(토큰) 삭제
+    const { cookies } = await import("next/headers");
+    const cookieStore = await cookies();
+    cookieStore.delete("accessToken");
+    cookieStore.delete("refreshToken");
+    cookieStore.delete("sessionId");
+
+    return { success: true, message: "회원 탈퇴가 완료되었습니다." };
+  } catch (error) {
+    if (
+      error instanceof Error &&
+      (error as Error & { digest?: string }).digest?.startsWith("NEXT_REDIRECT")
+    ) {
+      throw error;
+    }
+
+    if (isAxiosError(error)) {
+      const message =
+        error.response?.data?.message || "회원 탈퇴에 실패했습니다.";
+      console.error("[withdrawAction] API Error", {
+        status: error.response?.status,
+        message,
+      });
+      return { success: false, message };
+    }
+
+    console.error("[withdrawAction] Unexpected Error", error);
+    return { success: false, message: "알 수 없는 오류가 발생했습니다." };
+  }
+}
diff --git a/lib/actions/loginAction.ts b/lib/actions/loginAction.ts
index 316a378..fb5d350 100644
--- a/lib/actions/loginAction.ts
+++ b/lib/actions/loginAction.ts
@@ -30,55 +30,8 @@ export async function loginAction(
       body: { email, password },
     });
 
-    // 🍪 백엔드로부터 받은 쿠키가 있다면 브라우저에 배달해줍니다.
-    if (setCookie) {
-      const { cookies } = await import("next/headers");
-      const cookieStore = await cookies();
-
-      setCookie.forEach((cookieStr) => {
-        // Axios가 준 쿠키 문자열을 파싱합니다 (name=value; Path=/ ...)
-        const [nameValue, ...options] = cookieStr.split(";");
-        const [name, ...nameParts] = nameValue.split("=");
-        const value = nameParts.join("=");
-
-        const cookieOptions: {
-          path?: string;
-          httpOnly?: boolean;
-          secure?: boolean;
-          maxAge?: number;
-          expires?: Date;
-          sameSite?: "strict" | "lax" | "none" | boolean;
-          domain?: string;
-        } = {};
-
-        options.forEach((opt) => {
-          const [key, ...valueParts] = opt.trim().split("=");
-          const val = valueParts.join("=");
-          const k = key.toLowerCase();
-          if (k === "path") cookieOptions.path = val;
-          if (k === "httponly") cookieOptions.httpOnly = true;
-          if (k === "secure") cookieOptions.secure = true;
-          if (k === "max-age") cookieOptions.maxAge = parseInt(val);
-          if (k === "expires") cookieOptions.expires = new Date(val);
-          if (k === "domain") cookieOptions.domain = val;
-          if (k === "samesite")
-            cookieOptions.sameSite = val.toLowerCase() as
-              | "strict"
-              | "lax"
-              | "none";
-        });
-
-        // 배포 환경에서는 백엔드와 직접 통신하므로, 서브도메인 간 공유를 위해 명시적으로 도메인 설정
-        if (process.env.NODE_ENV === "production") {
-          cookieOptions.domain = ".comatching.site";
-        } else {
-          // 로컬에서는 도메인을 지워야 브라우저가 localhost에서 쿠키를 정상적으로 저장함
-          delete cookieOptions.domain;
-        }
-
-        cookieStore.set(name, value, cookieOptions);
-      });
-    }
+    // 🍪 serverApi.post 내부에서 response header의 set-cookie를 파싱하여
+    // 이미 cookieStore에 저장했으므로, 여기서 별도로 처리할 필요가 없습니다.
 
     if (finalUrl) {
       // https://comatching.site/onboarding -> /onboarding 추출