diff --git a/src/main/java/com/teamEWSN/gitdeun/repo/controller/RepoController.java b/src/main/java/com/teamEWSN/gitdeun/repo/controller/RepoController.java
index 6eb6968..eed00d3 100644
--- a/src/main/java/com/teamEWSN/gitdeun/repo/controller/RepoController.java
+++ b/src/main/java/com/teamEWSN/gitdeun/repo/controller/RepoController.java
@@ -18,8 +18,9 @@ public class RepoController {
     // 리포지토리 URL을 통한 등록 확인
     @GetMapping("/check")
     public ResponseEntity<RepoResponseDto> checkRepoExists(@RequestParam String url) {
-        RepoResponseDto response = repoService.findRepoByUrl(url);
-        return ResponseEntity.ok(response);
+        return repoService.findRepoByUrl(url) // Optional<RepoResponseDto>를 받음
+            .map(ResponseEntity::ok) // 값이 있으면 200 OK와 함께 body에 담아 반환
+            .orElseGet(() -> ResponseEntity.noContent().build()); // 값이 없으면 204 No Content 반환
     }
 
     // 리포지토리 정보 조회
diff --git a/src/main/java/com/teamEWSN/gitdeun/repo/dto/RepoResponseDto.java b/src/main/java/com/teamEWSN/gitdeun/repo/dto/RepoResponseDto.java
index 218143c..870c276 100644
--- a/src/main/java/com/teamEWSN/gitdeun/repo/dto/RepoResponseDto.java
+++ b/src/main/java/com/teamEWSN/gitdeun/repo/dto/RepoResponseDto.java
@@ -2,7 +2,6 @@
 
 import lombok.Builder;
 import lombok.Getter;
-import lombok.Setter;
 
 import java.time.LocalDateTime;
 
@@ -16,8 +15,5 @@ public class RepoResponseDto {
     private final String language;
     private final String description;
     private final LocalDateTime githubLastUpdatedAt;
-    private final LocalDateTime lastSyncedAt;
 
-    @Setter // Mapper의 @AfterMapping에서 이 값을 설정
-    private boolean updateNeeded; // 재동기화 필요 여부 플래그
 }
diff --git a/src/main/java/com/teamEWSN/gitdeun/repo/service/RepoService.java b/src/main/java/com/teamEWSN/gitdeun/repo/service/RepoService.java
index 544add6..6994c92 100644
--- a/src/main/java/com/teamEWSN/gitdeun/repo/service/RepoService.java
+++ b/src/main/java/com/teamEWSN/gitdeun/repo/service/RepoService.java
@@ -13,6 +13,7 @@
 import org.springframework.transaction.annotation.Transactional;
 
 import java.time.LocalDateTime;
+import java.util.Optional;
 
 @Service
 @RequiredArgsConstructor
@@ -23,22 +24,17 @@ public class RepoService {
     private final RepoMapper repoMapper;
     private final FastApiClient fastApiClient;
 
-    /**
-     * Mapper를 통해 'updateNeeded' 플래그가 포함된 DTO를 반환합니다.
-     */
+    // 레포지토리 ID로 정보 조회
     public RepoResponseDto findRepoById(Long repoId) {
         Repo repo = repoRepository.findById(repoId)
             .orElseThrow(() -> new GlobalException(ErrorCode.REPO_NOT_FOUND_BY_ID));
         return repoMapper.toResponseDto(repo);
     }
 
-    /**
-     * 리포지토리 URL로 정보를 조회
-     */
-    public RepoResponseDto findRepoByUrl(String url) {
-        Repo repo = repoRepository.findByGithubRepoUrl(url)
-            .orElseThrow(() -> new GlobalException(ErrorCode.REPO_NOT_FOUND_BY_URL));
-        return repoMapper.toResponseDto(repo);
+    // 리포지토리 URL을 통한 조회하여 등록 확인
+    public Optional<RepoResponseDto> findRepoByUrl(String url) {
+        return repoRepository.findByGithubRepoUrl(url)
+            .map(repoMapper::toResponseDto);
     }
 
     /**