Abstract: In this study, length-weight relationships, condition (K) factors of 409 rudd individual were determined between the period of December 2000-December 2001 in Sapanca Lake. According to sexes and seasons individuals which were examined about the length-weight relationships, mean weights and values of the condition (K) in the same length group were found no significance difference (p>0.05). The length-weight relationship of rudd were detected W= 0.004 L3.3731. The mean of value of condition (K) of rudd was determined 1.243.