Abstract: With the development of society and the increasing demand for ecological conservation, the traditional integrated reservoir operation aiming at flood control and profit fail to meet the diversified requirements. Hence, the implementation of multi-objective reservoir comprehensive optimization scheduling has become increasingly urgent. In order to achieve the optimization of the comprehensive benefits of Zaoshi Reservoir and balance the social, economic and ecological benefits, the optimization dispatching model of Zaoshi Reservoir for power generation, water supply and ecological requirements is established, which adopts the improved Multi-objective Shuffled Frog Leaping Differential Evolution Algorithm（MSFL-DEA） to calculate. And the scheme based on AHP and TOPSIS combined weight method is optimized according to different decision preferences. The results show that with the decrease in upstream inflow, the power generation benefit of the reservoir decreases most significantly, followed by the ecological benefit and water supply benefit. Under each inflow frequency, the competition relationship between ecological goal and power generation goal, water supply goal and ecological goal is more obvious, and the competition between power generation goal and water supply goal is relatively weak. Depending on decision preferences, four schemes of water supply priority, power generation priority, ecological priority and balance optimization are obtained. By comparison, it is found that the balanced scheme tends to compromise, and the water supply, ecology and power generation processes are relatively coordinated in each month of the year（P=75% as an example）. When inflow frequency is 50%, 75% and 95%, the annual power generation is 3.697, 2.981 and 2.155billion kWh, the water supply satisfaction is 0.871, 0.775 and 0.702, and the ecological satisfaction is 0.861, 0.699 and 0.615, respectively. The research results are conducive to improving the efficiency of water resources utilization, and can provide reference for the scientific operation decision of Zaoshi Reservoir.