The goal of this study was to determine the effects of ?-Agonist Zilpaterol hydrochloride on growth performance and carcass quality in Ross broiler chicken. Zilpaterol hydrochloride was daily fed at levels 0, 0.2, 0.25, 0.3 mg/kg of Live Body Weight (LBW) from d 25 to 45 of age. Eighty 308 Ross female broiler chickens were employed in a 20 d feeding trial of four replicates, five birds per treatment, in a completely randomized design. Birds were individually weighed on d 25 and 48 of the experiment. Blood samples were collected on d 25 and 45. Zilpaterol was withdrawn on d 45 and the birds weighted and slaughtered on d 48. Zilpaterol hydrochloride supplementation significantly decreased the feed intake and improved the Feed Conversation Ratio (FCR) in comparison with the control group (P<0.05). Treatment with 0.25 Zilpaterol hydrochloride led to the most appropriate FCR value (P<0.05). The effect of Zilpaterol hydrochloride on weight and carcass yield was not significant (P>0.05). Zilpaterol hydrochloride significantly affected plasma glucose and cholesterol concentration (P<0.05), and induced an increase in tissue protein along with a decrease in tissue fat of leg samples (P<0.05). It is finally concluded that Zilpaterol hydrochloride can improved boiler performance as well as its meat quality.