The present research aims to examine the relationship between diversity management and its effect on staffs’ affective commitment with study on mediation role of Transformational leadership and perceived justice in Qaen health network. In theoretical sector with integration of human resource management and performance theories and the theory of diversity and leadership, a theoretical model has been made. The main question of research is when the diversity management puts a positive effect on staffs’ affective commitment and why these two variables affect each other. The statistical population consists of all the staffs at the administrative sector in Qaen health network. After collecting data, the hypotheses were tested using the structural equation technique and software Smart PLS. the results from statistical analyses indicated that diversity management puts a positive effect on staffs’ affective commitment, but diversity management does not put a positive effect on perceived justice. Transformational leadership has a mediation role between diversity management and perceived justice. The perceived justice has a mediation role in effect of transformational leadership and staffs’ affective commitment. Further transformational leadership and perceived justice have a mediation role between the diversity management and affective commitment.