diff --git a/include/matrix4.h b/include/matrix4.h
index ed0e5751d..abac2215f 100644
--- a/include/matrix4.h
+++ b/include/matrix4.h
@@ -10,7 +10,6 @@
 #include "plane3d.h"
 #include "aabbox3d.h"
 #include "rect.h"
-#include "irrString.h"
 #include "IrrCompileConfig.h" // for IRRLICHT_API
 
 // enable this to keep track of changes to the matrix