Abstract: Tinghu Reservoir is the mother lake of Yanshan County, Wenshan prefecture. The local government has implemented several engineering projects to control water pollution of the lake. However, the water quality has become better, not reached the class Ⅲ yet, since all the projects haven't fully formed an effective countermeasures to promote the water quality. In 2022, Tinghu Lake has obtained an ecology-oriented development(EOD) project. The causes and protection countermeasures were put forward to provide scientific reference for the protection of the lake.