diff --git a/src/main/java/onepiece/dailysnapbackend/object/dto/CustomOAuth2User.java b/src/main/java/onepiece/dailysnapbackend/object/dto/CustomOAuth2User.java
index 3481cea..d539fc8 100644
--- a/src/main/java/onepiece/dailysnapbackend/object/dto/CustomOAuth2User.java
+++ b/src/main/java/onepiece/dailysnapbackend/object/dto/CustomOAuth2User.java
@@ -31,10 +31,6 @@ public Collection<? extends GrantedAuthority> getAuthorities() {
 
   @Override
   public String getName() {
-    return member.getNickname();
-  }
-
-  public String getUsername() {
     return member.getUsername();
   }
 
diff --git a/src/main/java/onepiece/dailysnapbackend/object/dto/SignInRequest.java b/src/main/java/onepiece/dailysnapbackend/object/dto/SignInRequest.java
index 0672e3a..ab4f55a 100644
--- a/src/main/java/onepiece/dailysnapbackend/object/dto/SignInRequest.java
+++ b/src/main/java/onepiece/dailysnapbackend/object/dto/SignInRequest.java
@@ -21,10 +21,6 @@ public class SignInRequest {
   @Schema(defaultValue = "example@naver.com")
   private String username;
 
-  @NotBlank(message = "accessToken을 입력하세요")
-  @Schema(defaultValue = "ya29.A0ARrdaMExampleAccessToken1234567890")
-  private String accessToken;
-
   @Schema(description = "생년월일 (선택)", defaultValue = "2004-01-01")
   private String birth;
 
diff --git a/src/main/java/onepiece/dailysnapbackend/service/MemberService.java b/src/main/java/onepiece/dailysnapbackend/service/MemberService.java
index 2778d02..9fe4492 100644
--- a/src/main/java/onepiece/dailysnapbackend/service/MemberService.java
+++ b/src/main/java/onepiece/dailysnapbackend/service/MemberService.java
@@ -65,15 +65,17 @@ public void socialSignIn(SignInRequest request, HttpServletResponse response) {
 
     // 응답 헤더에 토큰 설정
     response.setHeader("Authorization", "Bearer " + accessToken);
-    Cookie refreshTokenCookie = jwtUtil.createRefreshTokenCookie(refreshToken);
-    response.addCookie(refreshTokenCookie);
 
-    log.info("쿠키 설정: name={}, value={}, maxAge={}",
-        refreshTokenCookie.getName(), refreshTokenCookie.getValue(),
-        refreshTokenCookie.getMaxAge());
+    try {
+      response.setContentType("application/json");
+      response.getWriter().write(String.format("{\"refreshToken\": \"%s\"}", refreshToken));
+    } catch (IOException e) {
+      log.error("리프레시 토큰 응답 작성 중 오류 발생", e);
+      throw new CustomException(ErrorCode.INTERNAL_SERVER_ERROR);
+    }
 
-    response.getHeaderNames().forEach(name ->
-        log.info("Response Header: {}={}", name, response.getHeader(name)));
+    log.info("accessToken 헤더 설정 및 refreshToken body 응답 성공: accessToken={}, refreshToken={}: ", accessToken,
+        refreshToken);
   }
 
   // 리프레시 토큰을 통해 액세스 토큰 재발급
diff --git a/src/main/java/onepiece/dailysnapbackend/util/JwtUtil.java b/src/main/java/onepiece/dailysnapbackend/util/JwtUtil.java
index da1ee71..fd0881a 100644
--- a/src/main/java/onepiece/dailysnapbackend/util/JwtUtil.java
+++ b/src/main/java/onepiece/dailysnapbackend/util/JwtUtil.java
@@ -8,7 +8,6 @@
 import io.jsonwebtoken.io.Decoders;
 import io.jsonwebtoken.security.Keys;
 import io.jsonwebtoken.security.SignatureException;
-import jakarta.servlet.http.Cookie;
 import java.time.LocalDateTime;
 import java.util.Date;
 import java.util.concurrent.TimeUnit;
@@ -109,7 +108,7 @@ public String getCategory(String token) {
    * @return
    */
   public String createAccessToken(CustomOAuth2User customOAuth2User) {
-    log.info("엑세스 토큰 생성 중: 회원: {}", customOAuth2User.getUsername());
+    log.info("엑세스 토큰 생성 중: 회원: {}", customOAuth2User.getName());
     return createToken(ACCESS_CATEGORY, customOAuth2User, accessTokenExpTime);
   }
 
@@ -120,7 +119,7 @@ public String createAccessToken(CustomOAuth2User customOAuth2User) {
    * @return
    */
   public String createRefreshToken(CustomOAuth2User customOAuth2User) {
-    log.info("리프래시 토큰 생성 중: 회원: {}", customOAuth2User.getUsername());
+    log.info("리프래시 토큰 생성 중: 회원: {}", customOAuth2User.getName());
     return createToken(REFRESH_CATEGORY, customOAuth2User, refreshTokenExpTime);
   }
 
@@ -134,9 +133,9 @@ public String createRefreshToken(CustomOAuth2User customOAuth2User) {
   private String createToken(String category, CustomOAuth2User customOAuth2User, Long expiredAt) {
 
     return Jwts.builder()
-        .subject(customOAuth2User.getUsername())
+        .subject(customOAuth2User.getName())
         .claim("category", category)
-        .claim("username", customOAuth2User.getUsername())
+        .claim("username", customOAuth2User.getName())
         .claim("role", customOAuth2User.getMember().getRole())
         .claim("provider", customOAuth2User.getMember().getSocialPlatform())
         .issuer(issuer)
@@ -146,22 +145,6 @@ private String createToken(String category, CustomOAuth2User customOAuth2User, L
         .compact();
   }
 
-  /**
-   * refreshToken Cookie 생성
-   *
-   * @param refreshToken 리프레시 토큰
-   * @return 생성된 쿠키
-   */
-  public Cookie createRefreshTokenCookie(String refreshToken) {
-    Cookie cookie = new Cookie("refresh_token", refreshToken);
-    cookie.setHttpOnly(true);
-    cookie.setSecure(false);
-    cookie.setPath("/");
-    cookie.setMaxAge(Math.toIntExact(refreshTokenExpTime) / 1000);
-    cookie.setAttribute("SameSite", "Strict");
-    return cookie;
-  }
-
   /**
    * JWT 토큰 유효성 검사
    *