Abstract: To study the current status of the water quality of Erhai Lake, the monitoring information of the Jinhe National Automatic Water Quality Monitoring Station and the water quality monitoring data of Erhai Lake from January 2021 to April 2022 were applied and analyzed. The trend of the changes was examined using the comprehensive evaluation method and the single-factor evaluation method. The results showed that the water quality reached the standard of Class Ⅱ in 4 months and Class Ⅲ in 12 months. TP and TN have been effectively curbed since the implementation of the salvage mode was complemented in the Erhai Lake basin in 2016.