Abstract: Taking the landslide in southwestern China as an example, the impact of rainfall on the landslide with weak interlayer is studied by ABAQUS software. Combined with the actual construction process, it stimulated the deformational characteristics of the different landslide model, including the primary landslide, the landslide with supporting structures but without rainfall,as well as the landslide with supporting structures and rainfall. By comparing the stability coefficient of landslide under different rainfall infiltration intensity, the influence law of transient seepage effect of rainfall infiltration on the stability of landslide with weak interlayer is comprehensively evaluated, and the optimal design of drainage measures is proposed.