It is impossible to know the date of reforming resource taxes policies exactly.The problem how to extract exhaustible resources effectively under this uncertainty was studied.Resource extraction was divided into two processes,according to the reform date.The dynamic optimal model was built by using the idea of dynamic planning.The optimal model was solved based on optimal control theory.The optimal extraction path was found.The results show that (1) during initial period of resources extraction,resources extraction rate increases by increasing the probability of putting forward resources taxes policy (or increasing taxes rate).In the later date,it will conserve resources;(2) turning point is related with primal stock.Increasing the primal stock can postpone time of the turning point.