Abstract:City water-industry along Yangtze River has important impact on the river’s great protection. First of all, based on the present development situation of Great Protection of Yangtze River, as well as the current development status on the social third-party service in the field of city environmental protection and urban engineering construction, the demand for social third-party how to explore and innovate a new water-controlling mode under the new developing stage, is analyzed. And the theoretical basis on the new mode, i.e. city water-housekeeper, for social third-party participating in the construction of city water system along Yangtze River is studied. Then, the concept as well as connotation and basic features for city water-housekeeper are put forward and clarified. And basic element and framework system for the mode of city water-housekeeper are also established. Finally, application conditions as well as implementation road map for the mode of city water-housekeeper within Great Protection of Yangtze River is put forward, and its application progress in recent years as well as further practical promotion in the future concerning the mode is discussed.