The present trial aimed to throw the Light on the effect of dietary supplementation of protease enzyme on growth performance parameters and carcass quality of broiler chicks. Atotal number of 360 Cobb broiler chicks of mixed sex (one day old) where collected from a local Egyptian private hatchery were classified into 4 groups of three replicates (30 chicks/ replicate). The 1st group was fed diet containing soya bean meal 44%, 2nd group was fed diet containing soya bean meal 44%+ protease enzymes, 3rd group was fed diet containing soyabean meal 46% while 4th group was fed diet containing soyabean meal 46%+ protease. Water and feed were offered ad-libitum. All birds were systematically vaccinated against Newcastle, IB and Gumbro and other needed prophylactic measures. Results showed that, G4 showed increased in Final BW by (8.1%,7.58%,1.97%) , BWG by (8.3% ,7.7% ,1.97%) , FI by (1.88% , 0.88%, 0.06%) and FCR by (6.66% , 6.66% ,1.75%) than G1,G2 and G3 respectively. Carcass yields improved in protease supplemented groups where G4 showed increased in carcass relative weight than G3 by 1.07% and G2 showed increased in carcass relative weight than G1 by 2.71%. Also G4 showed increased in breast relative weight by (1.8%, 5.1%, 0.05%) and liver relative weight (12.56%, 5.9%, 3.36%) than G1, G2 and G3 respectively.