diff --git a/imperative/python/megengine/module/quantized/conv_bn.py b/imperative/python/megengine/module/quantized/conv_bn.py
index 4b3b5772b65988135d10e1056366d63be98d0669..2bfc070a49c4c250613e606f70c78e05972ee5dc 100644
--- a/imperative/python/megengine/module/quantized/conv_bn.py
+++ b/imperative/python/megengine/module/quantized/conv_bn.py
@@ -40,7 +40,9 @@ class _ConvBnActivation2d(Conv2d):
         )
         weight = w_fold.astype(qat_module.get_weight_dtype())
         qconv.weight = Parameter(weight.numpy(), name=qat_module.conv.weight.name)
-        qconv.bias = Parameter(b_fold.numpy(), name=qat_module.conv.bias.name)
+        qconv.bias = Parameter(b_fold.numpy())
+        if qat_module.conv.bias is not None:
+            qconv.bias.name = qat_module.conv.bias.name
         return qconv