Abstract:A new method is developed here to ensure the stability state of soil landslide by means of steel-plate piles. Two different ways are adopted for the analysis of work mechanism for steel-plate piles in the landslide. On the basis of the work mechanism of steel-plate piles,a new method is presented for searching the failure surfaces under limit shear situation in the landslide. A case study is conducted with limit equilibrium method and FEM. The numerical results are the same as the results of theoretical analysis. At the same time,the work mechanism of steel-plate piles could be expressed as following. The shape of slide surface is changed because of the existence of steel-plate piles in landslide,and the qualities of physical and mechanical parameters are improved indirectly because of the variation of shape of slide surface.