diff --git a/aos/flatbuffer_merge.cc b/aos/flatbuffer_merge.cc
index da0eb86..18a190f 100644
--- a/aos/flatbuffer_merge.cc
+++ b/aos/flatbuffer_merge.cc
@@ -1,6 +1,6 @@
 #include "aos/flatbuffer_merge.h"
 
-#include <stdio.h>
+#include <cstdio>
 
 #include "aos/flatbuffer_utils.h"
 #include "flatbuffers/flatbuffers.h"