The author of this paper applied the system dynamics method to analyze the complex relationship among all variables of comprehensive domestic water consumption in the future of Shanghai City. A system dynamics model of prediction for the comprehensive domestic water demand in the future of Shanghai City was set up to predict the change trend of the comprehensive domestic water consumption in the future of Shanghai City and probe the critical link and measures of water resources regulation. The purpose of this paper is to help improve the planning and management level of water resources sustainable utilization in Shanghai City, as well as providing references for the water resources planning and management of the developed cities or rapid urbanization area in China.