Abstract: Taking a power station in Lancang River Basin as an example, this paper uses a mathematical model and physical model to calculate and analyze the influence of different characteristic water levels on the sedimentation distribution at the end of the reservoir after the construction of the reservoir for the preliminary proposed schemes of different normal storage water levels and the operating water level during the flood season. The result shows that the accumulated siltation in the reservoir area increases with the increase in the operating water levels during the flood season and the normal storage water levels, and the influence of the operating water levels during the flood season is relatively large. The siltation distribution at the end of the reservoir presents a slight increase in siltation on the edge beach surface compared with the natural situation. The research results can provide a basis for reservoir characteristic water level selection and ecological protection.