The present work was aimed at determining the population structure, growth and mortality of Crucian carp (Carassius gibelio) population in Buldan Dam Lake, in the Gediz River basin. Total of 2325 specimens were caught monthly by the trammel nets during September 1995-August 1996. The sex composition was 99.44% females and 0.56% males. Maximum age group was determined as VI. Fork length and total weight of the specimens ranged from 9.7 to 25.5 cm and from 23.6 to 269.1 g. The length-weight relationship was estimated as W=0.031L(2.87) for all individuals. von Bertalanffy growth parameters were computed as L-infinity=31.66 cm, W-infinity=635.91 g, k=0.146 year(-1) and t(0) =-2.166 year. The ratios of total mortality, natural mortality and fishing mortality were calculated as 0.632 year(-1), 0.456 year(-1) and 0.176 year(-1), respectively.