The aim of this work was to investigate the effect of the dietary supplementation of different oil sources on the performance and physiological parameters of Nile tilapia. Seven isonitrogenous (30% crude protein) and isocaloric (4.40 kcal/g) experimental diets were formulated to containing different oils sources at the same levels (5%) including T1: cod liver oil; T2: poultry by product oil; T3: linseed oil; T4: corn oil; T5: 50% linseed oil + 50% poultry by product oil; T6: 50% corn oil + 50% poultry by product oil and control without oils. Fish (6.41 ± 0.01 g) were selected and randomly distributed at a rate of 15 fish/100-L aquarium in triplicates. The feeding rate was 3% of live body weight for 12 weeks. The chemical profiles of fatty acids were analyzed by Gas chromatographic analysis (GCFID). Results showed that the optimum growth-related parameters were obtained at T5. Fish fed T3 diet gave higher feed intake than other different oil  sources while fish fed T5 diet showed the best (lowest) for feed conversion ratio (FCR) in comparison to the control diet and other treatments. In regard to body composition, there were no significant differences with fish protein and lipid contents (P > 0.05) in all diets supplemented with different oil sources. Diets supplemented with different dietary oil sources showed the best physiological parameters in comparison with the control diet .The blood hemoglobin (Hb), red blood cells (RBCs) and hematocrit (Ht) were higher in Nile tilapia fed T5. Total serum protein and glucose in plasma were increased significantly in the group of fish consumed T5. T5 diet is more economic and reduced the oil cost in fish feed without any effect on growth performance or feed utilization. The reduction in feed cost compared with the control diet to produce one kg fish gain was highest in T2 diet followed by T5 diet.