diff --git a/douzero/evaluation/deep_agent.py b/douzero/evaluation/deep_agent.py
index df1fb4a..398bb54 100644
--- a/douzero/evaluation/deep_agent.py
+++ b/douzero/evaluation/deep_agent.py
@@ -30,19 +30,21 @@ def _load_model(position, model_path, model_type, use_legacy, use_lite, use_onnx
     # torch.save(model.state_dict(), model_path.replace(".ckpt", "_nobn.ckpt"))
     model.eval()
     model_path = model_path + '.onnx'
-    if use_onnx and not os.path.exists(model_path):
-        onnx_params = model.get_onnx_params(torch.device('cpu'))
-        torch.onnx.export(
-            model,
-            onnx_params['args'],
-            model_path,
-            export_params=True,
-            opset_version=10,
-            do_constant_folding=True,
-            input_names=onnx_params['input_names'],
-            output_names=onnx_params['output_names'],
-            dynamic_axes=onnx_params['dynamic_axes']
-        )
+    if use_onnx:
+        if not os.path.exists(model_path):
+            onnx_params = model.get_onnx_params(torch.device('cpu'))
+            torch.onnx.export(
+                model,
+                onnx_params['args'],
+                model_path,
+                export_params=True,
+                opset_version=10,
+                do_constant_folding=True,
+                input_names=onnx_params['input_names'],
+                output_names=onnx_params['output_names'],
+                dynamic_axes=onnx_params['dynamic_axes']
+            )
+        return None
 
     return model