The purpose of this study is to examine the effects of transformational leadership and organizational citizenship behavior. It also investigated the mediating effect of self leadership on the causal relationship between transformational leadership and organizational citizenship behavior. Research results, transformational leadership had a positive affected on the self leadership, The self leadership had a positive affected on organizational citizenship behavior. And transformational leadership did not make a significant impact on organizational citizenship behavior. Finally, the self leadership was a full mediator on the relationships between the transformational leadership and the organizational citizenship behavior. Based on these findings, the implications and the limitations of the study were presented including some directions for future studies.