【Aim】 To understand the species composition and alien fish invasion of Huizhou West Lake, a fish resource survey was conducted in February 2023. 【Method】 The Jaccard similarity index, similarity analysis, and non-metric multidimensional scaling (NMDS) were utilized to analyze the species composition, abundance differences, distribution patterns, community structure, and community similarity of alien fish in Huizhou West Lake. 【Result】 A total of 21 fish species were captured in this survey. Sixteen native fish species were found, including Cyprinus carpio, Carassius auratus, and Hypophthalmichthys harmandi. Five alien fish species were recorded, namely Pterygoplichthys pardalis, Tilapia zillii, Oreochromis niloticus, Sarotherodon galilaeus, and Labeo rohita. Alien fish species accounted for 45.36% of the total catch weight and 44.18% of the total catch tail. Additionally, Pterygoplichthys pardalis and Tilapia zillii were observed in relatively high proportions in terms of weight and quantity among the five alien fish species, suggesting the establishment of a significant population scale. The similarity analysis results showed that the average Jaccard similarity index value of Huizhou West Lake is 0.62, which is the "similarity" level, indicating that the fish communities are relatively similar at various stations. The clustering analysis results showed that at a similarity level of 78.73%, the fish community of Huizhou West Lake can be divided into four groups; however, statistically significant differences did not exist between these four groups (P>0.05). 【Conclusion】 Overall, the fish communities at each site of Huizhou West Lake are relatively similar. Huizhou West Lake has been invaded by Pterygoplichthys pardalis and Tilapia zillii, which appeared at each analyzed site. Therefore, corresponding prevention and control measures are urgently required.