Abstract: In the slope stability analysis, both the limit equilibrium method and the vector sum method assume that the slope instability is caused by shear failure, accordingly, it is difficult to correctly solve the safety factor of the complex slope with tensile failure at the upper part, while the global strength reduction method can obtain the safety factor, it is difficult to search for the complete sliding surface containing the tensile failure zone in the upper part of the slope. In view of the above problems, the dynamic strength reduction method is adopted to search for the sliding surface of slope, and an improved vector sum method which can take into account the tension failure and shear failure is proposed, so that the slope stability problem can be solved better. The results of three cases show that the dynamic strength reduction method can completely reflect the sliding surface of slopes, and the safety factor obtained by the improved vector sum method is basically the same as that by the global strength reduction method. The proposed method is applicable to the stability analysis of various types of slopes, such as soil, rock and soil-rock combinations, and is less affected by the main sliding direction, mesh size and model size, which helps to promote the further improvement of slope stability analysis methods.