Circulating water replenishment water and desalination water in a coking plant were supplied by river water instead of groundwater. The water quality characteristics of the river water were analyzed. After the river whater was treated by the process of“air flotation + coagulation high efficiency clarification + filtration + ultrafiltration”, the effluent water quality can reach the supplementary water quality of the open circulation cooling water system was met by the effluent water quality which is stupulated in the reuse of urban sewage for industrial use ‘GB/ T19923-2005’.