Abstract: The general situation of Yilonghu Lake was introduced. The water quality of the rivers and the wetlands were monitored. The results showed that the water quality of the entrance of Dashuihe River and Chenghe River could not reach the third grade of national standard. The water quality of Dashuihe River could reach the fifth grade of national standard, but the water quality of Chenghe River could not reach the fifth grade according to the water objectives of the thirteenth five-year plan of water environmental protection and treatment of Yilonghu Lake. Countermeasures were put forward.