In view of the problems of difficult establishment of effective displacement system and poor effect of water drive in Chang 8 reservoir of C335 area of JY oilfield, the reservoir development effect was evaluated comprehensively by reservoir pressure change, water drive law and effect characteristics. On this basis, combining with reservoir engineering and numerical simulation, this article formulated reasonable exploitation policy. The optimum injection⁃production ratio was 2.0, the flow pressure was 6.0 MPa, and the production rate was 0.7%. Finally, by comparing and forecasting the three schemes, the comprehensive scheme was the best.