Abstract: From thedata of copepod surveys made in 1962-1963,1974-1975 and 1979-1991 at StationsIand Ⅱ in Lake Donghu,Wuhan,the authors analyse the changes in species composition, standing crop of copepods.The number of copepod species decreased from 14 speciesin 1960's to 7 in 1990's,but the species composition became similar between the twostations. The standing crop of copepods was largely higher in the early and middle1980's.Before 1987,the standing crop was higher at Station I than that at Station Ⅱ,whilstthe reverse results were observed afterwards.Obvious changes also occurred in the horizontal distributions ofcopepods.Ecological factors influencing such changes are then discussed.