Abstract: Based on the analysis of control pattern of water diversion on the Yangtze River-Taihu lake water transfer prototype test, a model coupling water quantity and quality simulation and schedule is established to study the main water problem of Taihu basin.In view of the complexity of the model optimization, some rational and feasible solutions are put forward in the key links, including mainly the algorithm of the water quantity and quality numerical simulation model, the objective function and the constraint condition of the optimal operation model, and the coordination and connection between the simulation model and the optimization model.Aiming at the irrational distribution of the water diversion in the Yangtze River-Taihu lake water transfer prototype test, the rational scheduling mode of the water diversion from Wangyu river in special time period is studied, and the effect of the water diversion on the ecological environment of Taihu lake under different working conditions is emphatically analyzed.Results of the case study show very good feasibility of the methods above, and also provide theoretical reference for the quantitative study of the cross-regional integrated regulation of water quantity and quality.