diff --git a/version.h b/version.h
index d1c681f486..5b6b8e249a 100644
--- a/version.h
+++ b/version.h
@@ -4,7 +4,7 @@
 
 #define RUBY_RELEASE_YEAR 2017
 #define RUBY_RELEASE_MONTH 5
-#define RUBY_RELEASE_DAY 30
+#define RUBY_RELEASE_DAY 31
 
 #include "ruby/version.h"