diff --git a/tests/test_util_inspect.py b/tests/test_util_inspect.py
index cc67e37b3..a14c8a15f 100644
--- a/tests/test_util_inspect.py
+++ b/tests/test_util_inspect.py
@@ -670,6 +670,7 @@ def test_isattributedescriptor(app):
         pass
 
 
+@pytest.mark.sphinx(testroot='ext-autodoc')
 def test_isproperty(app):
     from target.functions import func
     from target.methods import Base