diff --git a/lib/_stream_transform.js b/lib/_stream_transform.js
index 1378c0c676e4ba..d58f112acfb95a 100644
--- a/lib/_stream_transform.js
+++ b/lib/_stream_transform.js
@@ -75,8 +75,7 @@ function afterTransform(stream, er, data) {
   if (data !== null && data !== undefined)
     stream.push(data);
 
-  if (cb)
-    cb(er);
+  cb(er);
 
   var rs = stream._readableState;
   rs.reading = false;