Based on the monitoring dates of Qionghai Lake at its four monitoring points,an assessment of water environment quality at these points has been made by the standard of surface water environment quality. The result shows that at Qinglong temple,the water quality is better,waters is Class Ⅱ;at the Second Waterworks and Qionghai Park,the water quality is average,waters is Class Ⅱ～Ⅲ：and at Haihe estuary,water quality is the worst,waters is Class Ⅳ.