diff --git a/norch/csrc/tensor.cpp b/norch/csrc/tensor.cpp
index 1fc95e1..1f374f8 100644
--- a/norch/csrc/tensor.cpp
+++ b/norch/csrc/tensor.cpp
@@ -211,6 +211,7 @@ extern "C" {
 
             float* result_data;
             cudaMalloc((void**)&result_data, size * sizeof(float));
+            cudaMemset(result_data, 0, size * sizeof(float));
             sum_tensor_cuda(tensor, result_data, axis);
             
             if (keepdim) {