Objective: The aim of the current study is to investigate the relationship among authentic leadership, occupation identity, perceived organizational support and teachers' knowledge sharing behavior. Methods: Using authentic leader-ship scale, knowledge sharing scale, teachers' occupation identity scale and perceived organizational support scale, we investigated 400 teachers, in which there were 321 valid questionnaires. Results: Authentic leadership was significantly and positively correlated with teachers' occupation identity, knowledge sharing behavior, and perceived organizational support.Occupation identity support partially mediated the relationship between authentic leadership and teachers' knowledge sharing behavior. Moreover, perceived organizational support moderated the relationship between occupation identity and knowledge sharing behavior. Conclusion: Through both mediating and moderating mechanism, the authentic leadership has significant effects on the teachers' knowledge sharing behavior.