diff --git a/reactos/lib/mesa32/src/drivers/windows/gdi/wmesa.c b/reactos/lib/mesa32/src/drivers/windows/gdi/wmesa.c
index 53d202251ad..9c0684813eb 100644
--- a/reactos/lib/mesa32/src/drivers/windows/gdi/wmesa.c
+++ b/reactos/lib/mesa32/src/drivers/windows/gdi/wmesa.c
@@ -72,7 +72,7 @@
 /* Stereo and parallel not tested for Mesa 4.0. */
 #define NO_STEREO
 #if !defined(NO_STEREO)
-#include "gl\glu.h"
+#include "GL/glu.h"
 #include "stereo.h"
 #endif