diff --git a/tests/utils/object_store/test_mlflow_object_store.py b/tests/utils/object_store/test_mlflow_object_store.py
index b7a5162afa..d1021de1c3 100644
--- a/tests/utils/object_store/test_mlflow_object_store.py
+++ b/tests/utils/object_store/test_mlflow_object_store.py
@@ -22,7 +22,7 @@
 @pytest.fixture(autouse=True)
 def setup_mlflow_tracking(monkeypatch):
     mlflow = pytest.importorskip('mlflow')
-    monkeypatch.setattr(mlflow.environment_variables.MLFLOW_TRACKING_URI, 'name', None)
+    monkeypatch.setenv(mlflow.environment_variables.MLFLOW_TRACKING_URI.name, '')
 
 
 def test_parse_dbfs_path():