diff --git a/Lib/tkinter/__init__.py b/Lib/tkinter/__init__.py
--- a/Lib/tkinter/__init__.py
+++ b/Lib/tkinter/__init__.py
@@ -150,7 +150,7 @@ def _tkerror(err):
 
 def _exit(code='0'):
     """Internal function. Calling it will throw the exception SystemExit."""
-    raise SystemExit(code)
+    raise SystemExit(int(code))
 
 _varnum = 0
 class Variable: