diff --git a/tutorial-contents/502_GPU.py b/tutorial-contents/502_GPU.py
index ba1c0dc..ba2d4e6 100644
--- a/tutorial-contents/502_GPU.py
+++ b/tutorial-contents/502_GPU.py
@@ -71,7 +71,7 @@ for epoch in range(EPOCH):
             # !!!!!!!! Change in here !!!!!!!!! #
             pred_y = torch.max(test_output, 1)[1].cuda().data.squeeze()  # move the computation in GPU
 
-            accuracy = sum(pred_y == test_y) / test_y.size(0)
+            accuracy = torch.sum(pred_y == test_y) / test_y.size(0)
             print('Epoch: ', epoch, '| train loss: %.4f' % loss.data[0], '| test accuracy: %.2f' % accuracy)