The fatty acid compositions of Tilapia rendalli, T. zilli and Oreochromis aurea reared in cages located in Seyhan Dam Lake, O. niloticus reared in freshwater ponds and Tilapia spp. from the Seyhan River were compared. The fatty acid levels of Tilapia spp. from the Seyhan River were significantly higher than those of the other groups (p < 0.05). Total omega-3 fatty acid values were significantly different for all groups and the highest level were found in Tilapia spp. (p < 0.05). The ratio of omega-3/ omega-6 for Tilapia spp., O. aurea, T. rendalli, T. zilli and O. niloticus were 1.95, 1.37, 1.29, 1.21 and 1. 12, respectively.