diff --git a/src/BowongModalFunctions/models/media_model.py b/src/BowongModalFunctions/models/media_model.py
index 7122f47..335bf02 100644
--- a/src/BowongModalFunctions/models/media_model.py
+++ b/src/BowongModalFunctions/models/media_model.py
@@ -57,11 +57,22 @@ class MediaSource(BaseModel):
             paths = media_url[5:].split('/')
             if len(paths) < 3:
                 raise ValidationError("URN-s3 格式错误")
-            return MediaSource(path='/'.join(paths[2:]),
+
+            media_source = MediaSource(path='/'.join(paths[2:]),
                                protocol=MediaProtocol.s3,
                                endpoint=paths[0],
                                bucket=paths[1],
                                urn=media_url)
+
+            s3_mount_path = config.S3_mount_dir
+            cache_path = os.path.join(s3_mount_path, media_source.cache_filepath)
+
+            # 校验媒体文件是否存在缓存中
+            if not os.path.exists(cache_path):
+                raise ValueError(f"媒体文件 {media_source.cache_filepath} 不存在于缓存中")
+
+            return media_source
+
         elif media_url.startswith('vod://'):  # vod://{endpoint}/{subAppId}/{fileId}
             paths = media_url[6:].split('/')
             if len(paths) < 3:
@@ -123,6 +134,7 @@ class MediaSource(BaseModel):
             case _:
                 return f"{self.protocol.value}/{self.endpoint}/{self.bucket}/{self.path}"
 
+
     @computed_field(description="文件后缀名")
     @cached_property
     def file_extension(self) -> Optional[str]:
@@ -187,3 +199,5 @@ class CacheResult(BaseModel):
 
 class DownloadResult(BaseModel):
     urls: List[str] = Field(description="下载链接")
+
+