diff --git a/reactos/include/wine/wownt32.h b/reactos/include/wine/wownt32.h
index 04fc96a105b..bf221ff69bc 100644
--- a/reactos/include/wine/wownt32.h
+++ b/reactos/include/wine/wownt32.h
@@ -25,5 +25,9 @@
 #define HWND_16(h32)      (LOWORD(h32))
 #endif
 
+#ifndef HWND_32
+#define HWND_32(h16)      ((HWND)      (ULONG_PTR)(h16))
+#endif
+
 #endif /* _WOWNT32_H_ */