diff --git a/docs/changelog/3500.bugfix.rst b/docs/changelog/3500.bugfix.rst
new file mode 100644
index 000000000..9df1cf05d
--- /dev/null
+++ b/docs/changelog/3500.bugfix.rst
@@ -0,0 +1,2 @@
+Make tox tests pass with Python 3.14.0a6
+- by :user:`hroncok`
diff --git a/tests/config/loader/test_str_convert.py b/tests/config/loader/test_str_convert.py
index 8540e2105..b06929f48 100644
--- a/tests/config/loader/test_str_convert.py
+++ b/tests/config/loader/test_str_convert.py
@@ -77,7 +77,7 @@ def test_str_convert_ok_py39(raw: str, value: Any, of_type: type[Any]) -> None:
     [
         ("a", TypeVar, TypeError, r"a cannot cast to .*typing.TypeVar.*"),
         ("3", Literal["1", "2"], ValueError, r"3 must be one of \('1', '2'\)"),
-        ("3", Union[str, int], TypeError, r"3 cannot cast to typing.Union\[str, int\]"),
+        ("3", Union[str, int], TypeError, r"3 cannot cast to (typing.Union\[str, int\]|str \| int)"),
         ("", Command, ValueError, r"attempting to parse '' into a command failed"),
     ],
 )