This study describes the length-weight (LWR) and length-length relationships of Capoeta sieboldii from Hirfanli Dam Lake, Turkey. Condition factor (K) was also calculated per fork length class of females and males. A total of 170 individuals was collected from monthly sampling between March 2004 and August 2005. LWRs of females and males were not statistically different with and within season. LWRs indicated isometric growth in both sexes. The slopes of LWRs were 3.171 for females and 2.980 for males. All correlations among fork length, total length, and standard length were highly significant (P<0.001, r(2)>0.92). The values of K ranged from 1.21 to 1.43 for females and from 1.12 to 1.36 for males.