Abstract:Macrozoobenthos were quarterly investigated in Lake Dongting in 2014, a total of 58 species belonging to 4 Phylums and 7 Classes were recorded, including 7 Oligochaeta, 28 Mollusca, 19 Insecta,1 Nematoda, 2 Hirudinea and 1 Gammaridae. The average density of macrozoobenthos was 187.4 ind./m2,of which mainly represented by mollusks. The density of mollusks, oligochaetes and aquatic insects was 88.7, 24.1 and 27.8 ind./m2,accounted for 47.3%, 12.9% and 14.9% of total density, respectively.The dominant species were Corbicula fluminea, Bellamya aeruginosa, Branchiura sowerbyi, Cryptochironomus digitatus and Gammaridae sp.. Canonical correspondence analysis showed water temperature and dissolved oxygen were highly correlated with macrozoobenthic community structure.Shannon-Wiener diversity index and Hilsenhoff's Biotic Index (BI)were calculated to assess the water quality of Lake Dongting,the evaluation result was light pollution and good respectively.The results of two indices were different to a certain extent, combined with ∑TLI, BI methods was more suitable for bioassessment in Lake Dongting.