diff --git a/dlls/wined3d/surface_base.c b/dlls/wined3d/surface_base.c
index d72f9d18352..906c7efe92c 100644
--- a/dlls/wined3d/surface_base.c
+++ b/dlls/wined3d/surface_base.c
@@ -93,7 +93,6 @@ HRESULT WINAPI IWineD3DBaseSurfaceImpl_QueryInterface(IWineD3DSurface *iface, RE
     TRACE("(%p)->(%s,%p)\n", This,debugstr_guid(riid),ppobj);
 
     if (IsEqualGUID(riid, &IID_IUnknown)
-        || IsEqualGUID(riid, &IID_IWineD3DBase)
         || IsEqualGUID(riid, &IID_IWineD3DSurface)) {
         IUnknown_AddRef((IUnknown*)iface);
         *ppobj = This;
diff --git a/include/wine/wined3d.idl b/include/wine/wined3d.idl
index 5a6a91fece1..82f5f76a463 100644
--- a/include/wine/wined3d.idl
+++ b/include/wine/wined3d.idl
@@ -2167,21 +2167,12 @@ typedef HRESULT (__stdcall *D3DCB_ENUMRESOURCES)(struct wined3d_resource *resour
 [
     object,
     local,
-    uuid(46799311-8e0e-40ce-b2ec-ddb99f18fcb4)
+    uuid(37cd5526-6f30-11d9-c687-00046142c14f)
 ]
-interface IWineD3DBase : IUnknown
+interface IWineD3DSurface : IUnknown
 {
     void *GetParent(
     );
-}
-
-[
-    object,
-    local,
-    uuid(37cd5526-6f30-11d9-c687-00046142c14f)
-]
-interface IWineD3DSurface : IWineD3DBase
-{
     HRESULT SetPrivateData(
         [in] REFGUID guid,
         [in] const void *data,