Abstract:There are some complicated landslides with several layers of slipping plane in the geotechnical engineering. Because of the alteration of engineering slope and the action of engineering structure,the slope structure and stress state will be changed. The original slide surface is not the most critical one,but the new critical slide surface will form based on it. Now little attention is paid to it. In this paper,a stability calculation method with the specified shear-out point is proposed,and a new search procedure is adopted to calculate factor of safety of each point on the slope surface. This method assumes that the most critical slide surfaces after construction is the combined sliding surfaces of the new and the original. Based on the method,the stability analysis is conducted for the multi-layer complex landslide. And the result is adopted to design supporting structure form and to determine the appropriate supporting position. Taking a practical engineering slope as an example,the application procedure of this method is described in details;and the design principle of supporting for large scale slide is suggested. The research result is meaningful for supporting design of complicated landslide.