diff --git a/src/sphinx_autodoc_typehints/__init__.py b/src/sphinx_autodoc_typehints/__init__.py
index 8aa7d4dc..2311133d 100644
--- a/src/sphinx_autodoc_typehints/__init__.py
+++ b/src/sphinx_autodoc_typehints/__init__.py
@@ -139,6 +139,9 @@ def format_annotation(annotation: Any, config: Config) -> str:  # noqa: C901 # t
     if module == "typing_extensions":
         module = "typing"
 
+    if module == "_io":
+        module = "io"
+
     full_name = f"{module}.{class_name}" if module != "builtins" else class_name
     fully_qualified: bool = getattr(config, "typehints_fully_qualified", False)
     prefix = "" if fully_qualified or full_name == class_name else "~"
diff --git a/tests/test_sphinx_autodoc_typehints.py b/tests/test_sphinx_autodoc_typehints.py
index acb483b3..2e213dd1 100644
--- a/tests/test_sphinx_autodoc_typehints.py
+++ b/tests/test_sphinx_autodoc_typehints.py
@@ -180,6 +180,7 @@ def test_parse_annotation(annotation: Any, module: str, class_name: str, args: t
     [
         (str, ":py:class:`str`"),
         (int, ":py:class:`int`"),
+        (StringIO, ":py:class:`~io.StringIO`"),
         (type(None), ":py:obj:`None`"),
         (type, ":py:class:`type`"),
         (collections.abc.Callable, ":py:class:`~collections.abc.Callable`"),