diff --git a/include/d3dx9core.h b/include/d3dx9core.h
index 5233317bc04..a04bced0227 100644
--- a/include/d3dx9core.h
+++ b/include/d3dx9core.h
@@ -16,7 +16,7 @@
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  */
 
-#include <d3dx9.h>
+#include "d3dx9.h"
 
 #ifndef __WINE_D3DX9CORE_H
 #define __WINE_D3DX9CORE_H
diff --git a/include/d3dx9effect.h b/include/d3dx9effect.h
index 3f527edbc53..8235794a310 100644
--- a/include/d3dx9effect.h
+++ b/include/d3dx9effect.h
@@ -16,7 +16,7 @@
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  */
 
-#include <d3dx9.h>
+#include "d3dx9.h"
 
 #ifndef __D3DX9EFFECT_H__
 #define __D3DX9EFFECT_H__
diff --git a/include/d3dx9math.h b/include/d3dx9math.h
index 2c41b73d423..bf03ca3abaa 100644
--- a/include/d3dx9math.h
+++ b/include/d3dx9math.h
@@ -17,7 +17,7 @@
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  */
 
-#include <d3dx9.h>
+#include "d3dx9.h"
 
 #ifndef __D3DX9MATH_H__
 #define __D3DX9MATH_H__
@@ -469,6 +469,6 @@ HRESULT WINAPI D3DXCreateMatrixStack(DWORD flags, ID3DXMatrixStack **stack);
 }
 #endif
 
-#include <d3dx9math.inl>
+#include "d3dx9math.inl"
 
 #endif /* __D3DX9MATH_H__ */
diff --git a/include/d3dx9mesh.h b/include/d3dx9mesh.h
index 47b0a3fc3fe..c9a2fd590c6 100644
--- a/include/d3dx9mesh.h
+++ b/include/d3dx9mesh.h
@@ -17,7 +17,7 @@
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  */
 
-#include <d3dx9.h>
+#include "d3dx9.h"
 
 #ifndef __WINE_D3DX9MESH_H
 #define __WINE_D3DX9MESH_H
diff --git a/include/d3dx9tex.h b/include/d3dx9tex.h
index 77f2d357e5a..3883165c67e 100644
--- a/include/d3dx9tex.h
+++ b/include/d3dx9tex.h
@@ -16,7 +16,7 @@
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  */
 
-#include <d3dx9.h>
+#include "d3dx9.h"
 
 #ifndef __WINE_D3DX9TEX_H
 #define __WINE_D3DX9TEX_H