The Banbianjie landslide is a typical rainfall accumulation landslide, and continues to develop after significant deformations and damages. In this paper, the geological conditions and deformation characteristics of the landslide were investigated and analysed, and the landslide deformation mechanism was described. A typical profile of the landslide was selected to establish a numerical model based on finite elements. The GeoStudio software was used to carry out seepage-stress coupling analysis and calculation of the landslide, and the stability of the landslide and the evolution characteristics of seepage and displacement fields under different rainfall conditions were investigated. The research results provide an important theoretical basis for the early warning and management of such landslides in the future.