Abstract:The landslide at Shiliushubao is a part of the Huanglashi landslide,a very important ancient landslide in Three Gorges Dam¢s headpond. Analyses are conducted on the mechanism of landslide by means of FEA based on the displacement-controlled method. In case that the slide surface is known,the study illustrates the application of the Katona contact element to modeling sliding surface. As comparison,another computation scheme is set, in which the sliding body is of the property of soil in the sliding band and there is no contact interface between the rock bed and the sliding body. In two manners,the safety factors are approximate but the failure mechanisms are quite different. This states that the property of soil in the sliding band controls the stability of landslide. The study also explains the reason why the safety factors obtained by conventional FEM are different from those by limit equilibrium methods.