diff --git a/wxPython/wx/lib/masked/maskededit.py b/wxPython/wx/lib/masked/maskededit.py
index 5a99f9ec43..25855d74e9 100644
--- a/wxPython/wx/lib/masked/maskededit.py
+++ b/wxPython/wx/lib/masked/maskededit.py
@@ -5298,6 +5298,8 @@ class MaskedEditMixin:
         """ Handler for EVT_KILL_FOCUS event.
         """
 ##        dbg('MaskedEditMixin::_OnKillFocus', 'isDate=',self._isDate, indent=1)
+        if self.IsBeingDeleted() or self.GetParent().IsBeingDeleted():
+            return 
         if self._mask and self._IsEditable():
             self._AdjustField(self._GetInsertionPoint())
             self._CheckValid()   ## Call valid handler