Problem statement:The purpose of this study is to explore the effects of two key factors (intrinsic reward and leadership style) of knowledge sharing behavior among academician in Iran. Approach: Primary data are collected via a questionnaire, which was adapted from previous literature. Data, which were collected from lecturers in the 10 of the best university from Tehran, Shiraz, Mashahd and Esfehan. Results: The results showed that an R² value of 0.191 indicating about 19. % of the variation in behavior to share can be explained by Leadership style and Reward system. The model is significant (F = 8.796, p< 0.01). Leadership style mentor was positively related to knowledge sharing behavior (β = 0.326, p< 0.01) and leadership style facilitator was not related to knowledge sharing behavior and so was Intrinsic Reward (β = 0.283, p< 0.01). The results of the study show that reward system, leadership style (mentor) are the two key factors which influencing the knowledge sharing behavior in the university. Discussion: This study is limited to Iranian academician. Hence, impact of culture should be considered in future studies. It is advised that future research should be designed for different countries in order to conduct a comparative study. Conclusion: These results provide some information that is useful to policy makers in developing countries in general, and particularly in Iran context by setting appropriate policies and strategies for promoting the knowledge sharing based on two key factors as leadership style and reward system.