The experiment aimed to evaluate the effect of different L-carnitine levels and amino acids in tilapia diets (control diet, 300 mg L-carnitine, 10 g lysine+5 g methionine, 15 g lysine+7 g methionine, 10 g lysine+5 g methionine+300 mg L-carnitine and 15 g lysine+7 g methionine + 300 mg L-carnitine) on growth performance, feed utilization and body composition of Nile tilapia. The diet contained (15g lysine + 7g methionine+300 mg L-carnitine/kg basal diet) significantly increased final body weight (BW), body length (BL), weight gain (WG), specific growth rate (SGR) and improved (reduced) feed intake, feed conversion ratio (FCR) while protein efficiency ratio was not significantly affected. Proximate analysis of whole fish showed that, the diet contained of (15g lysine + 7g methionine + 300 mg L- carnitine) significantly increased protein and decreased fat and ash while dry matter content of fish flesh was not significantly affected. It is concluded that, dietary L-carnitine supplementation (15 g lysine + 7 g methionine + 300 mg L-carnitine/kg/diet) improved growth and feed utilization, decrease tissue fat and increased tissue protein of Nile tilapia.