Abstract: From October 1986 to November 1987, in Danjiangkou Reservoir of Hanjiang Valley, 1192 specimen of five predator fish, Elopichthys bambusa, Culter mongolicus, C.alburnus, Silurus asotus, and Siniperca chuatsi were collected for the prensent study.Eighteen indices were selected in the calculation of exponential similarity coefficient of Hier-achical Clustering Methods.Thus, the five species were regarded as a guild of predators, and sub-divided into three growth groups, including large-sized group of E.bambusa, middle-sized group of Cullers, and S .chuatsi.and small-sized group of S. asotus.