This paper divided the leadership styles of the manager of a business unit of food service into transactional leadership and transformational leadership, and investigated how they influence the job attitudes of the employees by moderating of job characteristics. To achieve the purpose of this study, this paper analyzed the studies on leadership in business administration and the advanced empirical research. Independent variables in the study model are transactional and transformational leadership, dependent variables are additional efforts, organizational commitment and job satisfaction, and moderation variable is job characteristics. This paper gave operational definitions to the variables and set up the hypotheses to test the study model. The measuring tools based on the operational definitions are MLQ-5X, MLQ-1 and MSQ. The result of this study shows as follows:First, transformational leadership influences additional efforts, organizational commitment and job satisfaction more and positively than transactional leadership. Second, job characteristics moderates the relations between leadership, additional efforts, organizational commitment and job satisfaction. The moderation effects of job characteristics on transformational leadership are more than that on transactional leadership.