diff --git a/paddle/function/ConvOp.h b/paddle/function/ConvOp.h
index 92733bc1b76156269fd6c22799c60a1e8af1a492..b87808915ef2c665d9a2279470f70ef025318019 100644
--- a/paddle/function/ConvOp.h
+++ b/paddle/function/ConvOp.h
@@ -104,11 +104,11 @@ public:
 
 protected:
   size_t getFilterHeight(const TensorShape& filter) const {
-    filter[filter.ndims() - 2];
+    return filter[filter.ndims() - 2];
   }
 
   size_t getFilterWidth(const TensorShape& filter) const {
-    filter[filter.ndims() - 1];
+    return filter[filter.ndims() - 1];
   }
 
   std::vector<size_t> strides_;