Abstract: Poverty alleviation system change is in line with the evolution process of institutional change， based on the theory of institutional change， the motivation and path of poverty alleviation institutional change were analyzed. The results show that the expected return is greater than the expected cost profit factor is the basic reason of poverty alleviation and institutional change， technological factors reduce the transaction cost of institutional change， informal institution for poverty alleviation system change provides a psychological basis and consciousness. The implementation path of poverty alleviation institutional change is mandatory innovation carried out from top to bottom by the government. On this basis， it is proposed that the institutional construction of the rule of law， the cultivation of endogenous power in the cultural level， and the integration of various forces in the governance pattern are the paths to further optimize the poverty alleviation system， so as to improve the performance of the poverty alleviation system and realize the modernization of rural agriculture and the overall revitalization of rural areas.

Key words: institutional change, poverty alleviation system, targeted poverty reduction