diff --git a/sagemaker-core/src/sagemaker/core/experiments/run.py b/sagemaker-core/src/sagemaker/core/experiments/run.py
index 2082fc9f5b..79e78188a1 100644
--- a/sagemaker-core/src/sagemaker/core/experiments/run.py
+++ b/sagemaker-core/src/sagemaker/core/experiments/run.py
@@ -69,6 +69,8 @@
 TRIAL_NAME_TEMPLATE = "Default-Run-Group-{}"
 MAX_RUN_TC_ARTIFACTS_LEN = 30
 MAX_NAME_LEN_IN_BACKEND = 120
+# UpdateTrialComponent rejects a Status.Message longer than this.
+MAX_STATUS_MESSAGE_LEN = 1024
 EXPERIMENT_NAME = "ExperimentName"
 TRIAL_NAME = "TrialName"
 RUN_NAME = "RunName"
@@ -760,7 +762,7 @@ def __exit__(self, exc_type, exc_value, exc_traceback):
         if exc_value:
             self._trial_component.status = _api_types.TrialComponentStatus(
                 primary_status=_TrialComponentStatusType.Failed.value,
-                message=str(exc_value),
+                message=(str(exc_value) or "")[:MAX_STATUS_MESSAGE_LEN],
             )
         else:
             self._trial_component.status = _api_types.TrialComponentStatus(
diff --git a/sagemaker-core/tests/unit/experiments/test_run_exit.py b/sagemaker-core/tests/unit/experiments/test_run_exit.py
new file mode 100644
index 0000000000..294b45c974
--- /dev/null
+++ b/sagemaker-core/tests/unit/experiments/test_run_exit.py
@@ -0,0 +1,49 @@
+# Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"). You
+# may not use this file except in compliance with the License. A copy of
+# the License is located at
+#
+#     http://aws.amazon.com/apache2.0/
+#
+# or in the "license" file accompanying this file. This file is
+# distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF
+# ANY KIND, either express or implied. See the License for the specific
+# language governing permissions and limitations under the License.
+"""Status recorded by Run.__exit__."""
+
+from __future__ import absolute_import
+
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+from sagemaker.core.experiments.run import Run
+from sagemaker.core.experiments.trial_component import _TrialComponent
+
+
+def _run_with_trial_component():
+    # Skip the network-bound __init__; __exit__ only needs these attributes.
+    run = Run.__new__(Run)
+    run._trial_component = _TrialComponent(
+        sagemaker_session=MagicMock(), trial_component_name="trial-component"
+    )
+    run._in_load = False
+    run._inside_init_context = True
+    run._inside_load_context = False
+    return run
+
+
+@pytest.mark.parametrize("message_length, expected_length", [(2000, 1024), (10, 10)])
+def test_exit_with_exception_limits_status_message_to_api_maximum(message_length, expected_length):
+    """UpdateTrialComponent rejects Status.Message longer than 1024 characters."""
+    run = _run_with_trial_component()
+    error = RuntimeError("x" * message_length)
+
+    with patch.object(Run, "close") as mock_close:
+        run.__exit__(type(error), error, None)
+
+    status = run._trial_component.status
+    assert status.primary_status == "Failed"
+    assert len(status.message) == expected_length
+    mock_close.assert_called_once()