Abstract: To investagte the diversity of aquatic insects in Anhui Shengjin Lake Wetland of International Importance, a quatrat survey was conducted in the middle of each month from September 2022 to August 2023 across five habitats: Phragmites australis marsh, Carex humida marsh, rice fields, woodland areas, and floodplains. The study focused on analyzing the species composition, population abundance, diversity, and similarity of aquatic insect community in these distinct ecosystems. The results showed that a total of 11 515 aquatic insect specimens were collected, spanning 8 orders, 20 families, and 59 species. Among them, Odonata, Hemiptera, and Diptera were identified as the dominant group, while Pantala flavescens, Micronecta quauriseta and eight other aquatic insects were dominant species across all five habitat types. Besides, significant differences in biodiversity indices were observed among different habitat types. Specifically, the Shannon-Wiener diversity index, Simpson diversity index, Margalef's richness index, and Pielou's evenness index all reached their lowest values in woodland areas. Generalized linear mixed model (GLMM) analysis revealed that water transparency was the dominant water environmental factor affecting diversity indices. Non-metric multidimensional scaling (NMDS) analysis further demonstrated distinct differences in aquatic insect community composition between woodland and the other four habitat types.