diff --git a/PPOCRLabel/PPOCRLabel.py b/PPOCRLabel/PPOCRLabel.py
index 390c2b159575bf1c60387e42b5be3d917ba845f7..0a3ae1cb3b8fc004aa7c48dc86b6546a80e17a0f 100644
--- a/PPOCRLabel/PPOCRLabel.py
+++ b/PPOCRLabel/PPOCRLabel.py
@@ -2715,6 +2715,9 @@ class MainWindow(QMainWindow):
 
             self._update_shape_color(shape)
             self.keyDialog.addLabelHistory(key_text)
+            
+        # save changed shape
+        self.setDirty()
 
     def undoShapeEdit(self):
         self.canvas.restoreShape()