diff --git a/re2/make_unicode_casefold.py b/re2/make_unicode_casefold.py
index 0cf0d3592..803adbd42 100755
--- a/re2/make_unicode_casefold.py
+++ b/re2/make_unicode_casefold.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/python3
 # coding=utf-8
 #
 # Copyright 2008 The RE2 Authors.  All Rights Reserved.
diff --git a/re2/make_unicode_groups.py b/re2/make_unicode_groups.py
index 46aef40cf..cbe822ad9 100755
--- a/re2/make_unicode_groups.py
+++ b/re2/make_unicode_groups.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/python3
 # Copyright 2008 The RE2 Authors.  All Rights Reserved.
 # Use of this source code is governed by a BSD-style
 # license that can be found in the LICENSE file.