Abstract: Rational development and utilization of water resources is a problem dealting with many factors and multi-purposes. Based on the multiobjective theory the author presents a basic principle for the rational distribution of water resources and develop an objective planning model for optimization distribution of inland water resources in northwestern arid zone. With catchment as unit the objective factors of sub-objectives were found by means of Analytical Hierarchy Process. It has achieved a satisfactory result through practical calculation to main basin system of the Heine River.