B425 block of Shengli Oilfield has the characteristics of poor reservoir physical properties and strong heterogeneity. After hydraulic fracturing, there are problems such as large inter-layer productivity differences, inadequate reservoir utilization, and short production increase effective period. Aiming at post-fracturing productivity, an optimization method for fracturing fracture parameters of heterogeneous reservoirs in the B425 block is proposed. A fine geological model of the fourth member of Shahejie Formation in B425 block is established by longitudinal fine layering, grid direction adjustment and local grid refinement. Through the establishment of a typical injection-production well group model, the production data before and after the fracturing of the oil well is historically matched. With the goal of single well productivity after fracturing, the fracture length and conductivity are optimized. The research results show that the reservoir physical properties of the four sand layers in the fourth member of the Shahejie Formation in the B425 block are quite different. The reservoir physical properties of the first and second sand groups are better than those in the third and fourth sand groups. Analyzing the effects of different fracture parameters on the productivity of oil wells after fracturing, the optimal section lengths of the three fractured intervals are 90, 70, and 80 m, and the optimal fracture conductivity is 20, 25, and 30 D.cm. This method can significantly improve the effect of hydraulic fracturing and stimulation, and provide a reference for the optimization of fracture parameters of heterogeneous reservoirs.