Based on the Drucker-Prager model, this paper takes Majiagou landslide as the object of analysis. Based on the horizontal resistance and displacement, the finite element analysis software ABAQUS is used to analyze the deformation law of the anti-slide piles of different positions during the development of the landslides under seepage forces in the fluctuation of reservoir water level. The studies show that the horizontal resistance and displacement of the anti-slide piles soil increase with the increase of seepage forces when the reservoir water level fluctuates. From 0 to 60 days, the deformation process of the landslide undergoes instantaneous loading and unloading deformation, stress adjustment deformation, stress steady growth deformation of the three deformation processes. The displacement rate of the landslide decreases continuously from 0.5 to 40 days, and the landslide is in slow creep stage. The displacement rate of landslide tends to be stable from 40 to 100 days, landslide is in constant creep stage. When the displacement rate of the landslide is stable, the soil deformation is in a slow and continuous state, which shows the creep characteristics of Majiagou landslide. The horizontal resistance and displacement of before and behind the anti-slide piles are time-dependent.