Abstract: The river ecological compensation mechanism of Dianchi Basin in Kunming City has been implemented since April 2017,providing a pilot experience for the establishment and implementation of the ecological compensation mechanism for small river basins at the municipal level.In order to evaluate the effectiveness of the ecological compensation mechanism in improving river water quality, we adopted a combination of quantitative and qualitative methods to analyze the construction and operation of the ecological compensation mechanism in the Dianchi Basin, evaluate the benefits of water quality improvement, summarize the improvement effects and existing problems, and propose countermeasures for optimizing the mechanism.The results show that since the implementation of the river ecological compensation mechanism, the water environment of rivers and the lakes in Dianchi Basin, and the water quality monitoring network, as well as the water environment management capacity have all been improved significantly.The mechanism is generally effective.However, there are still some problems such as evaluation index to be optimized, incomplete compensation scope, single compensation method, as well as supervision and public participation to be strengthened.Therefore, it is necessary to further improve the ecological compensation mechanism for rivers in Dianchi Basin, raise compensation funds in a diversified way, improve the performance evaluation system, so as to promote the formation of replicated ecological compensation models of Dianchi Basin.