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Erhai Lake is the second largest freshwater lake on the Yunnan Plateau, Southwest China. In recent decades, a number of exotic fi sh species have been introduced into the lake and the fi sh community has changed considerably. We evaluated the status of the fi sh community based on surveys with multimesh gillnet, trap net, and benthic fyke-net between May 2009 and April 2012. In addition, we evaluated the change in the community using historical data describing the fi sh community and fi shery harvest. The current fi sh community is dominated by small-sized fi shes, including Pseudorasbora parva , Rhinogobius giurinus , Micropercops swinhonis , Hemiculter leucisculus , and Rhinogobius cliffordpopei . These accounted for 87.7% of the 22 546 total specimens collected. Omnivorous and carnivorous species dominated the community. A canonical correspondence analysis (CCA) plot revealed that the distribution of fi shes in the lake is infl uenced by aquatic plants, water temperature, pH, and season. The abundance of indigenous species has declined sharply, and a majority of endemic species have been extirpated from the lake (a decrease from seven to two species). In contrast, the number of exotic species has increased since the 1960s to a total of 22 at present. The fi shery harvest decreased initially following the 1960s, but has since increased due to the introduction of non-native fi sh and stocking of native fi sh. The fi shery harvest was signifi cantly correlated with total nitrogen, not total phosphorus, during the past 20 years. Based on our results, we discuss recommendations for the restoration and conservation of the fi sh resources in Erhai Lake.