diff --git a/optimum/exporters/utils.py b/optimum/exporters/utils.py
index 59e053ee444..d386c09b7d8 100644
--- a/optimum/exporters/utils.py
+++ b/optimum/exporters/utils.py
@@ -690,7 +690,7 @@ def check_dummy_inputs_are_allowed(
             The model input names.
     """
 
-    forward = model.forward if is_torch_available() and isinstance(model, nn.Module) else model.call
+    forward = model.forward if is_torch_available() and isinstance(model, torch.nn.Module) else model.call
     forward_parameters = signature(forward).parameters
     forward_inputs_set = set(forward_parameters.keys())
     dummy_input_names = set(dummy_input_names)