With the tight control of the water level of the non-flood season (0.6m/d) in the Three Gorges Reservoir area, nearly 1000 landslides are prevented from a large-scale sliding into the river. However, the control of the reservoir drawdown rate in flood falling period limits the flood control and the benefits of hydroelectric power generation to a certain extent. In this paper, the feasibility of raising the reservoir drawdown rate in non-flood season is studied, Seep/W and SLOPE modules in Geo-studio are used to analyze the seepage and evaluate the stability of landslide on the ditch side. On this basis, the reservoir drawdown rate in flood falling period can be determined, which has significant practical significance and scientific value for the adjustment of drawdown rate in the Three Gorges Reservoir area.