Three hundred unsexed 1-day old Cobb chicks with initial live weight of 44.70±0.04 g, were randomly distributed into five experimental groups with three replicate in each, with 20 chicks (5x3x20). They used to study the effects of different supplementation levels of Allicin (0, 3, 6, 9, and 12 mg/Kg diet) on broiler performance, some blood metabolites and antioxidants stats. Broilers were reared for 5 weeks in an open house system and were offered both feed and clean drinking water ad-libitum. Throughout the test phase, body weight (BW), We kept track of weight gain (BWG), feed intake (FI), and feed conversion ratio (FCR). Results showed that, performance traits includes body weight, weight gain, and feed conversion ratio of broiler chicks was improved significantly (P≤0.05) by increasing the supplementation levels of allicin for (3 to 12 mg/kg diet). In addition, broilers received different supplementation levels of allicin showed significant (P≤0.05) improvement in some blood biochemical (total protein, albumin, triglyceride and low density of lipids). The same direction was observed for antioxidant indices (TAC and MDA). From the previous results it could be conducted that, allicin can be used at the level of (12 mg /kg diet) in the diet of broiler to improve performance traits and physiological status without any negative effects.