This paper takes the main city of Kunshan and its surrounding areas as the research object. On the basis of reasonable determination of water quality improvement target and the hydrological and hydraulic data of river basin and region, water diversion and drainage pattern, water supply source and water quantity are determined macroscopically. Combined with existing planning and current situation, scenarios of live water flow scheme are designed. Besides, the microscopic simulation verification and decision analysis are carried out through MIKE11 hydrodynamic water quality mathematical model. The construction layout and scheduling scheme of live water diversion project are put forward. The purpose of this paper is to provide some reference for other cities in plain river network area implementing water diversion to improve the urban water environment.