diff --git a/dlls/ddraw/d3dviewport.c b/dlls/ddraw/d3dviewport.c
index 0309ba3383158bf93651cdcecb0a0cdebb6172bd..b4115f304e53d751cc83bf329011e9b61f062bac 100644
--- a/dlls/ddraw/d3dviewport.c
+++ b/dlls/ddraw/d3dviewport.c
@@ -131,6 +131,7 @@ ULONG WINAPI IDirect3DViewport2Impl_Release(LPDIRECT3DVIEWPORT2 iface)
   FIXME("(%p)->() decrementing from %lu.\n", This, This->ref );
 
   if (!--(This->ref)) {
+    HeapFree(GetProcessHeap(),0,This->private);
     HeapFree(GetProcessHeap(),0,This);
     return 0;
   }