diff --git a/paddle/gserver/layers/MKLDNNLayer.h b/paddle/gserver/layers/MKLDNNLayer.h
index 9b54c95b55cc9b503de5ff527ac983eb4752ddb0..2c21a5b2aaecb17a52a5de9a98664068f2255d83 100644
--- a/paddle/gserver/layers/MKLDNNLayer.h
+++ b/paddle/gserver/layers/MKLDNNLayer.h
@@ -339,9 +339,13 @@ private:
    * clear all grad
    */
   void clearGrads() {
-    output_.grad->zeroMem();
+    if (output_.grad) {
+      output_.grad->zeroMem();
+    }
     for (size_t i = 0; i < outputOtherDevice_.size(); i++) {
-      outputOtherDevice_[i].grad->zeroMem();
+      if (outputOtherDevice_[i].grad) {
+        outputOtherDevice_[i].grad->zeroMem();
+      }
     }
   }