Abstract: Benthic macroinvertebrates in Honghu Lake were investigated from April 1988to October 1989.In total,71 species(genera)of zoobenthos were collected, of which, 20 species were molluses,10 species aquatic oligochaetes, 26 genera aquaticinsects and 15 species others. Differences were observed in the standing-crops of zoobenthos among differentsample areas, and so were the seasonal changes in the standing-crops. The averagevalues of density and biomass of zoobenthos in the whole lake were 502 ind./m2,35.47g/m2 respectively. The community structure of zoobenthos was used for biological assessmentof water quality.It revealed that the water in Honghu Lake was polluted to light-moderate extent by organic materials.Furthermore, chemical monitoring of water quality was identical with biological assessment.