diff --git a/api/app/schemas/app_schema.py b/api/app/schemas/app_schema.py
index eeb73a01..24475d5b 100644
--- a/api/app/schemas/app_schema.py
+++ b/api/app/schemas/app_schema.py
@@ -433,7 +433,7 @@ class AppChatRequest(BaseModel):
     user_id: Optional[str] = Field(default=None, description="用户ID（用于会话管理）")
     variables: Optional[Dict[str, Any]] = Field(default=None, description="自定义变量参数值")
     stream: bool = Field(default=False, description="是否流式返回")
-    files: Optional[List[FileInput]] = Field(default=None, description="附件列表（支持多文件）")
+    files: Optional[List[FileInput]] = Field(default=list, description="附件列表（支持多文件）")
 
 
 class DraftRunRequest(BaseModel):