Abstract: Based on the characters of water dispatching project in the main steam of Yellow River,this paper presents the principle and purpose of the sustainable water dispatching,and establishes a combined decomposition-coordination models for water dispatching of the main steam of Yellow River,which consists of the operation model of cascade reservoirs in the up reaches,the combined operation model of Sanmenxia reservoir and Xiaolangdi Reservoir in the middle reaches,the spatial al-location model,and the optimization model of scenario evaluation.The model presented is advantageous in efficiency and flexibility of development,easy for application and clear data flow.The solving strategy of the combined models is also presented1 The preliminary applications show that the model is successful and efficient.