diff --git a/swift/loss_scale/utils.py b/swift/loss_scale/utils.py
index d8e8b1a8e3..7cd336375f 100644
--- a/swift/loss_scale/utils.py
+++ b/swift/loss_scale/utils.py
@@ -4,7 +4,7 @@
 from swift.template import split_str_parts_by
 
 
-def calculate_loss_scale(query: str,
+def calculate_loss_scale(query: Optional[str],
                          response: str,
                          response_loss_scale_map: Dict[str, list],
                          query_loss_scale_map: Optional[Dict[str, list]] = None) -> Tuple[List[str], List[float]]:
@@ -28,7 +28,7 @@ def calculate_loss_scale(query: str,
         A tuple of agent response parts and their weights.
     """
     # query loss scale map
-    if query_loss_scale_map is not None:
+    if query_loss_scale_map is not None and query is not None:
         for key in query_loss_scale_map.keys():
             if key in query:
                 if isinstance(query_loss_scale_map[key], (float, int)):