<p>The construction of many large-scale hydropower projects has affected the geological and hydrological conditions of the reservoir area, and frequent landslides have seriously threatened human lives and property and the safety of engineering operations. Existing research results are more and more researches on the impact of reservoir bank slopes on water storage, but the impact of dumping deformation rock mass by reservoir water action is still small. Therefore, this article focuses on the deformation evolution process of dumping deformation body under the action of the rise and fall of the reservoir water level. And stability is worthy of in-depth study and discussion. This paper uses the seep/w module of the finite element software Geo-studio to analyze the seepage characteristics of the groundwater in the yellow lawn deformed body under different reservoir water amplitude rates during the operation of the reservoir (within the normal storage level of 1130m and the dead water level of 1120m)., And then analyze its stability characteristics based on the slope/w module coupling, and comprehensively propose water level scheduling recommendations. Studies have shown that the seepage field changes inside the bank slope are different for different reservoir water amplitude rates, and the seepage field changes will lag behind the changes in the reservoir water level. When the reservoir water level rises, the bank slope stability coefficient Fs first increases and then decreases. The stability coefficient after the seepage flow stabilizes is the long-term stability coefficient after the water storage. When the reservoir water level drops, the bank slope stability coefficient Fs first decreases and then increases. When the stability coefficient reaches the minimum value, it starts to increase slowly, and finally stabilizes. When the water level drops too fast, the transient stability coefficient is lower than the final steady-state stability coefficient. If the water level drops too fast and the transient Fs is less than 1, the deformed body may undergo instability and damage, and water level scheduling is proposed. The process should be carried out at a low rate and uniform speed to reduce the impact of the hysteresis effect of groundwater. This research can provide reference for similar projects.</p>