diff --git a/mmcv/ops/masked_conv.py b/mmcv/ops/masked_conv.py
index e00a98b99..275b503a4 100644
--- a/mmcv/ops/masked_conv.py
+++ b/mmcv/ops/masked_conv.py
@@ -58,6 +58,8 @@ class MaskedConv2dFunction(Function):
             if mask.size()[1:] != output.size()[2:]:
                 raise ValueError(
                     'The mask is inconsistent with the shape of output_conv.')
+            mask = mask > 0
+            mask = mask.type(output.dtype)
             output = output * mask
             return output