Based on the survey of macrozoobenthos from the Yangtze River estuary in summer during 2011—2014,this paper analyzes inter-annual variation of species composition,abundance and biomass.The results showed that a total of 60 species were collected in 2011,58 species in 2012,78 species in 2013,and 83 species in 2014.During 2011—2013,the mean abundance and the mean biomass decreased year by year.Meanwhile,the mean abundance and the mean biomass in the diluted water region of the Yangtze River estuary were noticeably higher than those of the Yangtze River estuary.Both the mean abundance and the mean biomass,however,rose again significantly in 2014.The biodiversity index (H'),richness index (D) and evenness index (J') were basically stable,slightly lower in 2012 and exhibiting an overall recovery trend later.The dominant species were Heteromastus filiformis,Cossurella dimorpha,and Gammarus sp.Polychaetes were the dominant group every year except in 2013,in which no dominant species was detected.The inter-annual variation in community structure was relatively large and the community components showed a trend of increasing abundance year by year.The results of this paper provide a scientific basis for further study of environmental change and macrozoobenthos community succession in the Yangtze River estuary.