Evaporative cooling with watery pad and exhaust fan has been broadly studied in past years. Although such cooling system has been demonstrated for higher energy saving than traditional air conditioning machines, it also innately inherits drawback of temperature gradient along airflow direction. In this paper, we will practically survey the performance of our evaporative cooling system. According to experimental results, the problem of uneven temperature distribution might not be insolvable; the second half area without the effectiveness of humid air could be cooled by forced ventilation. Our survey indicates that exhaust fan can nearly cools the rest of half airflow path. This makes evaporative cooling system becoming more feasible for greenhouse designs in the future.