diff --git a/torch_npu/npu/amp/grad_scaler.py b/torch_npu/npu/amp/grad_scaler.py
index 831e9b66cb2e0a74fafab1ef1107656e9ae8239c..f56a39b9df154a9c4d0b50059146813bbf337541 100644
--- a/torch_npu/npu/amp/grad_scaler.py
+++ b/torch_npu/npu/amp/grad_scaler.py
@@ -456,7 +456,11 @@ class GradScaler(BaseGradScaler):
                                "from a disabled instance of GradScaler." + pta_error(ErrCode.VALUE))
 
         super(GradScaler, self).load_state_dict(state_dict)
-        self._dynamic = state_dict["dynamic"]
+        
+        if 'dynamic' in state_dict:
+            self._dynamic = state_dict["dynamic"]
+        else:
+            warnings.warn("`dynamic` variable not found in loss_scaler's state_dict, default value will be used")
 
     @staticmethod
     def get_npu_overflow_flag():