diff --git a/tests/ut/python/dataset/test_config.py b/tests/ut/python/dataset/test_config.py
index 08b20a28fe9..7a12eff3139 100644
--- a/tests/ut/python/dataset/test_config.py
+++ b/tests/ut/python/dataset/test_config.py
@@ -21,6 +21,7 @@ import glob
 import numpy as np
 
 import mindspore.dataset as ds
+import mindspore.dataset.engine.iterators as it
 import mindspore.dataset.transforms.py_transforms
 import mindspore.dataset.vision.c_transforms as c_vision
 import mindspore.dataset.vision.py_transforms as py_vision
@@ -311,6 +312,10 @@ def test_deterministic_python_seed_multi_thread():
     """
     logger.info("test_deterministic_python_seed_multi_thread")
 
+    # Sometimes there are some ITERATORS left in ITERATORS_LIST when run all UTs together,
+    # and cause core dump and blocking in this UT. Add cleanup() here to fix it.
+    it._cleanup()  # pylint: disable=W0212
+
     # Save original configuration values
     num_parallel_workers_original = ds.config.get_num_parallel_workers()
     seed_original = ds.config.get_seed()