diff --git a/src/document/UBDocumentController.cpp b/src/document/UBDocumentController.cpp
index 6af01d96..6be0b05a 100644
--- a/src/document/UBDocumentController.cpp
+++ b/src/document/UBDocumentController.cpp
@@ -52,7 +52,7 @@
 
 
 #include "gui/UBThumbnailView.h"
-#include "gui/UBDocumentTreeWidget.h"
+//#include "gui/UBDocumentTreeWidget.h"
 #include "gui/UBMousePressFilter.h"
 #include "gui/UBMessageWindow.h"
 #include "gui/UBMainWindow.h"