diff --git a/ecs/crm-datafetch/tests/test_set_datetime_period_process.py b/ecs/crm-datafetch/tests/test_set_datetime_period_process.py
index 87a44a30..6315bb7b 100644
--- a/ecs/crm-datafetch/tests/test_set_datetime_period_process.py
+++ b/ecs/crm-datafetch/tests/test_set_datetime_period_process.py
@@ -59,6 +59,8 @@ class TestSetDatetimePeriodProcess:
 
         # 返り値の期待値チェック
         assert isinstance(actual_last_fetch_datetime, LastFetchDatetime), '最終取得日時オブジェクトクラスのインスタンスが返却される'
+        assert actual_last_fetch_datetime.last_fetch_datetime_from == '1999-01-01T00:00:00.000Z'
+        assert actual_last_fetch_datetime.last_fetch_datetime_to == '2100-12-31T23:59:59.000Z'
 
         # ログの確認
         assert generate_log_message_tuple(log_message='I-DATE-01 [Account] のデータ取得期間設定処理を開始します') in caplog.record_tuples