The population growth and economic development as well as the ever increasing demand for domestic and production water gave rise to a growing contradiction between water supply and demand. Low efficiency of water use and severe water waste have not been effectively controlled. It is imperative to allocate water fairly and reasonably, improve water use efficiency and alleviate the imbalance of water supply and demand. A semi-structural and multiobjective fuzzy optimal selection model is established and is taken to allocate water resources among all regions in Ganjiang River Basin. The approach is aimed at providing a viable method for the water allocation in the basin.