Abstract: Traditionally water allocation in a river basin was wholly determined by the balance calculation of water demand and supply from upstream to dow nstream in Xinjiang - This approach has the great dfficulty to solve theconflicts bet ween different tributaries, reaches and sectors. In addition, because the river basin has complicatedwater system, this approach can only get several water allocation schemes according to the river basin planningThe decisionmaker frequently faces the problem to get the rational water allocation scheme. Therefore the paperbuild a integrated modeling system to meet such requirement. The modeling system designed includes five com*ponents with the strong functions for regulating the conflicts. The Graphic User Interface are designed to facili-tate the decision maker to control key parameters of river basin planning, water diversion projects and waterusers. 'The GIS is also embedded in the system to display the results and assist the decision maker to find the water deficit in right place.At last the rational water allocation scheme can be obtained through the repeated modeling with regulation.

Key words: Xinjiang, river basin, water resources allocation, modeling system