With the rapid development of China's economy and the continuous improvement of people's living standards, the discharge of industrial and agricultural wastewater and domestic sewage increases year by year, causing serious pollution of urban river courses. Urban river pollution mainly comes from domestic sewage, industrial wastewater, agricultural wastewater and rainwater. The deterioration of water environment caused by serious river pollution not only affects the normal development of cities, but also poses a serious threat to the health of urban residents and urban ecological security. It has become the key to ensure the sustainable development of cities to solve the problem of water pollution and restore the ecological and social functions of river courses. Online monitoring of river water quality is one of the most important means of pollution prevention and water quality warning. Buoy-type monitoring system can observe meteorological and hydrological contents in all weather, continuously and at fixed points, and transmit data to shore stations in real time. It is a kind of modern water quality monitoring means. Buoys are highly difficult integration of probe water quality analysis instrument, data acquisition and transmission system, power supply system, etc., which can be directly put into lakes, reservoirs, farms and other environments, with practicability, flexibility and expansibility.