diff --git a/lib/_stream_writable.js b/lib/_stream_writable.js
index 02481739250635..f5f05486d233a9 100644
--- a/lib/_stream_writable.js
+++ b/lib/_stream_writable.js
@@ -249,9 +249,7 @@ function validChunk(stream, state, chunk, cb) {
 
   if (chunk === null) {
     er = new errors.TypeError('ERR_STREAM_NULL_VALUES');
-  } else if (typeof chunk !== 'string' &&
-             chunk !== undefined &&
-             !state.objectMode) {
+  } else if (typeof chunk !== 'string' && !state.objectMode) {
     er = new errors.TypeError('ERR_INVALID_ARG_TYPE', 'chunk',
                               ['string', 'Buffer']);
   }