diff --git a/lib/php/src/protocol/TBinarySerializer.php b/lib/php/src/protocol/TBinarySerializer.php
index 2913d32..542233b 100644
--- a/lib/php/src/protocol/TBinarySerializer.php
+++ b/lib/php/src/protocol/TBinarySerializer.php
@@ -48,6 +48,7 @@
     } else {
       $object->write($protocol);
     }
+    $protocol->getTransport()->flush();
     return $transport->getBuffer();
   }