diff --git a/src/msw/frame.cpp b/src/msw/frame.cpp
index 18933e21b3..08d33b8b77 100644
--- a/src/msw/frame.cpp
+++ b/src/msw/frame.cpp
@@ -37,6 +37,7 @@
     #include "wx/dialog.h"
     #include "wx/settings.h"
     #include "wx/dcclient.h"
+    #include "wx/mdi.h"
 #endif // WX_PRECOMP
 
 #include "wx/msw/private.h"