Abstract: Influenced by the reservoir regulation and storage in the upper reaches of the Yangtze River and the increase of water demand in the middle and lower reaches of the Yangtze River, the inflow and outflow of the Three Gorges Reservoir have changed significantly during the impoundment period compared with the initial stage. It is difficult for the reservoir to impound water according to the preliminary design mode, especially in the years when the inflow is low.In order to ensure that the Three Gorges Reservoir successfully completes the 175 m water storage goal, and to ensure that the comprehensive benefits of the Three Gorges Reservoir are brought into full play, a large number of studies have been carried out to optimize and adjust the water storage mode. Since 2010, the Three Gorges Rservoir has reached 175 m water storage goal for the ninth consecutive year by adopting a new water storage scheme, which shows that the optimized water storage mode can improve the reservoir full storage rate. Based on the analysis of the 175 m impoundment practice of the Three Gorges Reservoir in 2018, it is shows that the excessive inflow from late September to early October may cause the reservoir tail inundation risk. In order to reduce the reservoir tail inundation risk caused by excessive inflow during the impoundment period, the corresponding measures are put forward for reference.