Abstract：A new approach based on the method of slices to analyze the stability of slopes with non-circular slip surface is presented. Generally，when a sliding body is discretized to slices，the slices¢ nodes represent the slip surface. So the basic approach of this algorithm is to move the nodes randomly and uses a non-numerical method，such as simulated annealing(SA) to induct the current surface to the most potential critical slip surface. There are several merits of this method：it doesn¢t need to configure searching domains；it can figure out the shape of slip surfaces naturally even under the geometrically and geologically complicated realistic situation without presuming the surface shape previously and it performs with high efficiency since each time the change focuses on only one node. Several test problems are listed and demonstrate that this algorithm can pick out the global critical surface. It also testifies that the shape of potential failure surface can be circular arc，straight lines，or combination of them. Finally，more effective searching strategies are discussed.
