diff --git a/src/slic3r/GUI/Preferences.hpp b/src/slic3r/GUI/Preferences.hpp
index fdfa39455..01f116760 100644
--- a/src/slic3r/GUI/Preferences.hpp
+++ b/src/slic3r/GUI/Preferences.hpp
@@ -5,6 +5,7 @@
 #include "GUI_Utils.hpp"
 
 #include <wx/dialog.h>
+#include <wx/timer.h>
 #include <map>
 
 class wxColourPickerCtrl;