diff --git a/python/google/protobuf/pyext/message.cc b/python/google/protobuf/pyext/message.cc
index 920c17d8d138..78bcc99cc0b9 100644
--- a/python/google/protobuf/pyext/message.cc
+++ b/python/google/protobuf/pyext/message.cc
@@ -49,6 +49,7 @@
 #ifndef Py_TYPE
 #define Py_TYPE(ob) (((PyObject*)(ob))->ob_type)
 #endif
+#include <google/protobuf/arena.h>
 #include <google/protobuf/stubs/common.h>
 #include <google/protobuf/stubs/logging.h>
 #include <google/protobuf/io/coded_stream.h>