A study was conducted to evaluate the effects of different kinds of dietary lipid on growth and fatty acid composition of juvenile cobia(Rachycentron canadum).Five semi-purified diets containing 43.5% crude protein with 20.0 MJ available energy/kg were supplemented with 7.5% of either beef tallow(BT),soybean(SO),peanut(PO),corn(CO)or menhaden fish oils (MFO).The diets were fed to triplicate groups of 20 fish(8.3±0.5g)for 56 days.Results showed that fish fed the diets containing beef tallow,corn and peanut oils had significantly(P<0.05)reduced SGR and SGR was best for fish fed the diet contain menhaden fish oil.Fish fed the ~ soybean oil diet had the second highest weight gain,followed by fish on peanut oil,corn oil and beef tallow diets,respectively.Fatty acid composition in cobia muscle and livers was significantly reflected by that of the dietary lipids,especially for the diets containing unsaturated fatty acid.These data indicate that MFO showed a higher value for juvenile cobia and that n-3 highly unsaturated fatty acids such as eicosapentaenoic(20∶5n-3)and docosahexaenoic(22∶6n-3)acids in MFO are essential for maximum growth of cobia.