diff --git a/tests/test_pytest_mock.py b/tests/test_pytest_mock.py
index 1a51636..14187c2 100644
--- a/tests/test_pytest_mock.py
+++ b/tests/test_pytest_mock.py
@@ -524,6 +524,7 @@ def __call__(self, x):
     assert spy.spy_return_list == [20]
 
 
+@pytest.mark.asyncio
 async def test_instance_async_method_spy(mocker: MockerFixture) -> None:
     class Foo:
         async def bar(self, arg):