Abstract: This experiment was conducted to assess the effect of replacing Poultry Fat (PF) with Fish Oil (FO) in broiler diets on Fatty Acid (FA) composition and sensory quality of broiler meat. Three percents oil in 4 diets were altered with replacing PF by FO in completely randomized design at four treatments with 4 replicates (T1 = 3% PF, T2 = 2% PF+1% FO, T3 = 1% PF+2% FO and T4 =3% FO) and were given ad libitum to the birds fed throughout the growth period. The fatty acids profile and quality of the breast tissue were determined. Removing PF from diet by replacement of FO decreased total saturated (TSAT) (p<0.01) and total monounsaturated FA (TMUFA) (p<0.001). The amounts of total polyunsaturated FA (TPUFA) were significantly increased when FO level was increased (p<0.001). Altering of substituting PF by FO resulted in higher values of Linolenic Acid (LNA) and long-chain n-3 PUFA (C22:6n-3, C22:5n-3, C20:5n-3) in the breast tissue (p<0.001)and therefore decrease in the n-6: n-3 ratio (p<0.001). In the sensory quality evaluations (flavor and normal smell), the meat of T3 was acceptable. Therefore, with replacing PF by FO in diets of broiler chicks, meat of T3 could be enriched without significant sensory losses, which may improve nutritional content and promote of human health.