This research was carried out from November 1992 to November 1993 in the Altmkaya Dam Lake of Bafra of Samsun province. During the study, totally 236 Barbus plebejus escherichi Steindachner, 1897 were examined. The purpose of the present study was to determine some biological features such as age and size composition, length-weight relationship, growth rates. The age composition of specimens ranged from II to VI and age-group IV.was maximum with ratio of 52.54%. THe percentages were calculated as 62.82% for females and 37.18% for males in the stock. The determined minumum and maximum fork length were 196 and 404 mm, weight were 95.60 and 691.02 g. The weight-length relationship and growth equations were estimated as: W=0.0192L2.8507, Lt=51.0619[1-e-0.937(t+0.06052)] and Wt=1422.6918[1-e-0.1937(t+0.6052)]2.8507, respectively.