diff --git a/src/sagemaker/experiments/run.py b/src/sagemaker/experiments/run.py
index 1492b6bafa..b34c19bb3a 100644
--- a/src/sagemaker/experiments/run.py
+++ b/src/sagemaker/experiments/run.py
@@ -648,7 +648,8 @@ def _append_run_tc_label_to_tags(tags: Optional[List[Dict[str, str]]] = None) ->
         """
         if not tags:
             tags = []
-        tags.append(RUN_TC_TAG)
+        if RUN_TC_TAG not in tags:
+            tags.append(RUN_TC_TAG)
         return tags
 
     def __enter__(self):
diff --git a/tests/unit/sagemaker/experiments/test_run.py b/tests/unit/sagemaker/experiments/test_run.py
index 0e4ebee181..6fc671197e 100644
--- a/tests/unit/sagemaker/experiments/test_run.py
+++ b/tests/unit/sagemaker/experiments/test_run.py
@@ -912,6 +912,11 @@ def test_append_run_tc_label_to_tags():
     assert len(ret) == 2
     assert expected_tc_tag in ret
 
+    tags = [expected_tc_tag]
+    ret = Run._append_run_tc_label_to_tags(tags)
+    assert len(ret) == 1
+    assert expected_tc_tag in ret
+
 
 def _verify_tc_status_before_enter_init(trial_component):
     assert not trial_component.start_time