Focusing on the problems faced by urban river networks, such as the lack of connectivity, deterioration of water quality and difficulty in river network regulation, a new comprehensive improvement method of water environment in urban river networks is proposed based on the techniques of running water circulation coupled with efficient purification. Some technical problems demanding immediate attention in the process of river network regulation are discussed, which are overall water supply regulation technique for urban river networks, quantitative and integrated purification technique, refined water environment simulation and information mutual feedback mechanism and information centralization and global processing scheme. Based on these problems, we expounds the connotation and overall requirements of the purification system connecting urban river network with running water circulation under the new situation, and puts forward the framework covering four aspects of the system, including river network restoration, river network water purification, river network water flow-water quality simulation evaluation and water quality online monitoring. The key technical issues such as the coupling technique of urban river network water dynamic connection regulation-quantitative integrated purification, the coupling technique of river network water dynamic monitoring-refined simulation, as well as the global information management and connection of river network water environment. This study can shed some light on the direction of future planning and management of urban river networks.