In order to un derstand the dynamics and composition of metazooplankton community structure at the estuary of Maixi River in Lake Baihua,metazooplankton was investigated from August 2009 to August 2011.The results showed that there were 29 rotifer species with abundance ranging from 0.16 to 837.80 ind./L.Only two kinds of copepoda,Mesocyclops thermocyclopoides and Harpacticella sp.were detected,the abundance range from 0 to 642.75 ind./L.9 cladocera species were detected with abundances from 0 to 31.20 ind./L.Metazoan zooplankton abundance was mainly composed by rotifer and copepods.The proportion of rotifer abundance was from 4.09% to 100%,comparing to the percentage of copepods being from 0 to 95.64%.Asplanchna priodonta, Asplanchna brightwelli,Brachionus diversicornis were the dominant species for rotifer,whose highest abundance reached 424.88,392.20 and 61.99 ind./L,respectively;Bosmina longirostris as the dominant specie of cladocera,with a maximum abundance of 27.93 ind./L.Rotifer abundance was significant positive related to transparency,total nitrogen,nitrate nitrogen;while cladocera abundance exhibited a significant positive correlation with transparency and nitrate nitrogen,but significant negative correlation with the temperature.