diff --git a/tests/process-reboot-cause_test.py b/tests/process-reboot-cause_test.py
index 25b22e58..063984d8 100644
--- a/tests/process-reboot-cause_test.py
+++ b/tests/process-reboot-cause_test.py
@@ -67,4 +67,26 @@ def test_invalid_json(self, mock_geteuid, mock_stdout, mock_is_smartswitch, mock
 
         # Check invalid JSON handling
         output = mock_stdout.getvalue()
-        self.assertTrue(mock_connector.called)
\ No newline at end of file
+        self.assertTrue(mock_connector.called)
+
+    @patch("process_reboot_cause.swsscommon.SonicV2Connector")
+    @patch("process_reboot_cause.device_info.get_dpu_list", return_value=["dpu1", "dpu2"])
+    def test_update_dpu_reboot_cause_to_chassis_state_db(self, mock_get_dpu_list, mock_connector):
+        # Mock DB
+        mock_db = MagicMock()
+        mock_connector.return_value = mock_db
+
+        # Call the function
+        process_reboot_cause.update_dpu_reboot_cause_to_chassis_state_db()
+
+        # Verify DB interactions for each DPU
+        mock_db.set.assert_any_call(mock_db.CHASSIS_STATE_DB, "REBOOT_CAUSE|DPU1", "cause", "PowerLoss")
+        mock_db.set.assert_any_call(mock_db.CHASSIS_STATE_DB, "REBOOT_CAUSE|DPU1", "time", "2024-12-10")
+
+    @patch("process_reboot_cause.device_info.get_dpu_list", return_value=[])
+    def test_invalid_dpu_list(self, mock_get_dpu_list):
+        # Call the function with an empty DPU list
+        process_reboot_cause.update_dpu_reboot_cause_to_chassis_state_db()
+
+        # Ensure no DB interactions occur when DPU list is empty
+        mock_get_dpu_list.assert_called_once()