The principal role of National Parks are providing unusual scenery and recreation opportunity and conserving biodiversity. Promoting utilization of them also contributes to visitors’ health and culture of our society. Visiting parks might make a lasting impression on visitors, and then satisfied visitors could affirm loyalty to parks and get psychological benefits. There have been less investigations regarding with the psychological benefits of National Parks in Japan. Thus, we conducted a questionnaire surveys at four popular Mountaion National Parks in Japan, Shiretoko, Nikko, Kamikochi, and Tateyama, to identify the relationship among visitors’ impressions, satisfaction, loyalty and benefit. As a result, “nature appreciation,” “enriching the mind,” and “environmental awareness and understanding” are considered as great benefits due to visiting parks. Types of benefits are different by activities visitors attended. We also found the significant relationship between impression and satisfaction or benefit. The benefit has larger influence on their willingness to revisit and recommendations to others than satisfaction. Promoting National Parks utilization should pay attention to offering impressive experience in parks and the effect on visitors’ loyalty.