Abstract: To evaluate the effect of the Keping Uplift on the Selibuya Fault in the southern margin of the Bachu Uplift during thrusting, and the consequent fault sealing variation, three-dimensional geological modeling and tectonic stress field numerical simulation of the Selibuya Fault have been carried out. Through the data obtained by three-dimensional stress simulation, it has been concluded that, as the result of SE-direction stress of the Keping Uplift, the sliding ratio on the Selibuya Fault plane is variant. The overall sliding ratio is small while that of the middle and southern parts are relatively bigger. The sliding ratio variation is determined by the space geometry of fault. Based on the analysis of the Xianbazha and Yasongdi oil-gas reservoirs which lie in the fault-fold belt flanked the Selibuya Fault, it is thought that the effect of SE-direction stress is limited to the middle and southern parts of the Selibuya Fault. As to the Yasongdi oil-gas reservoir which lies in the middle part of the Selibuya Fault, the SE-direction stress improves the vertical communication and the charge of oil and gas, which is also beneficial to late accumulation.