The purpose of this study is to evaluate the mediating role of organizational justice between transformational leadership and OCB. The statistical population in this research includes 136 employees of the Social Security Organization. The sampling method is simple random sampling method and using Cochran formula the sample size is equal to 100 people. The data for this study was collected using a questionnaire that its validity was tested. To determine the reliability and validity of the questionnaires, content validity and Cronbach's alpha coefficient were used. The reliability coefficient for the Bass and Olive transformation leadership questionnaire (1997), is equal to 0.89, and for Organizational Justice questionnaire Nihof and Mooren (1993), is equal to 0.79; and for OCB Questionnaire (2001) equals to 0.81. In this research, structural relationships model was used for data analysis. Lisrel statistical software was used to analyze the data and to test the hypotheses and other analyzes of this study. The results showed that there is a significant relationship between transformational leadership and organizational justice. Also, there is a significant relationship between transformational leadership and organizational citizenship behavior, but the mediating role of organizational justice in the relationship between transformational leadership and organizational citizenship behavior was not confirmed.
