diff --git a/pets-be/internal/service/file.go b/pets-be/internal/service/file.go
index e108749..4c187cd 100644
--- a/pets-be/internal/service/file.go
+++ b/pets-be/internal/service/file.go
@@ -8,6 +8,7 @@ import (
 	"io"
 	"path"
 	"strings"
+	"time"
 
 	"github.com/sundynix/pets-be/internal/model"
 )
@@ -41,7 +42,9 @@ func (s *Service) UploadFile(reader io.Reader, filename, contentType string) (*m
 	if contentType == "" {
 		contentType = "application/octet-stream"
 	}
-	objectName := "files/" + md5hex + ext
+	// 按上传月份分文件夹：uploads/2026-07/<md5>.jpg。文件名仍用 md5 保证唯一。
+	// 同内容命中上面的去重直接复用，不会因为跨月再传一份
+	objectName := "uploads/" + time.Now().Format("2006-01") + "/" + md5hex + ext
 	url, err := s.storage.Upload(objectName, bytes.NewReader(data), int64(len(data)), contentType)
 	if err != nil {
 		return nil, err