diff --git a/Common/StringUtils.h b/Common/StringUtils.h
index 3485bfb9da1610378d63bd576fa111abf9d30cda..66c543bb8a645888a6fcc654d607f6479db60596 100644
--- a/Common/StringUtils.h
+++ b/Common/StringUtils.h
@@ -3,8 +3,8 @@
 // See the LICENSE.txt file for license information. Please report all
 // bugs and problems to <gmsh@geuz.org>.
 
-#ifndef _STRING_UTIL_H_
-#define _STRING_UTIL_H_
+#ifndef _STRING_UTILS_H_
+#define _STRING_UTILS_H_
 
 #include <string.h>
 #include <string>