Abstract:By using the strength reduction method in the analysis on slope stability,the soil strength is reduced,so that the numerical non-convergence occurs,and the safety factor is obtained. The strength reduction method is applied to 3D analysis on slope stability in this paper. At the same time,with a case study,the result analyzed by the traditional method is compared with that by strength reduction FEM,and the results of 2D and 3D analyses are analyzed. It is indicated that strength reduction FEM is appropriate to stability analysis of slope,and 3D analysis should be used in stability analysis of slope if it is possible.