After the construction of the Three Gorges Dam, geological hazards frequently occur, and landslides are the most widespread disasters in the reservoir area. The rapid landslide induced by rainfall is an important natural disaster in the Three Gorges Reservoir area. The rapid landslide induced by rainfall is an important natural disaster in the Three Gorges Reservoir area. Rainfall can cause changes in pore water pressure. To study the slope stability with the pore water pressure, Yangjialing landslide located in Three Gorges Reservoir area is performed using stress-seepage-slope stability coupled analysis after water drawdown. Meanwhile the phreatic line from the simulation results is compared with the analytical solution. Lower permeability and higher drawdown velocity will result in a higher pore water pressure and it is harmful to the slope stability. The zone with smaller permeability will spend longer time to change from saturated state to unsaturated state if the water level descends at the same speed. Through the research of this paper, the main factors of landslide are obtained, which lays a theoretical foundation for the prevention of landslide in the Three Gorges Reservoir area.