In this paper, based on the fact of water resources shortage, environmental degradation in Chanba River basin, using multi-objective optimization theory, we established the ecology-oriented water resources optimal allocation model and achieved the coupling between water quantity and quality. According to supply and demand of water resources in two levels of years (2020, 2030) and the guaranteed rate 75%, developed model parameters (coefficients), called the optimization function to solve it. The model is applied to Chanba River basin, indicating that the model is reasonable, efficient algorithms The optimal allocation model and the results reflect the concept of sustainable development for ecological, economic efficiency and help to improve water supply reliability, the sustainable use of water resources planning and management provides a basis for decision making.