A total number of 192 unsexed 1-day old Arbor Acres broiler chicks were randomly distributed in 8 treatments in a factorial design distribution(2×4) in two feed forms (recommended vs low density diet as 2% crude protein and 100 Kcal ME/Kg) and four enzyme mixtures (un-supplemented, Nu3Lease, Kem Zyme^® Plus Dry and Fra Zyme^® Ms Dry at the level of 0.05% of each) to evaluate growth performance, carcass traits and economical efficiency. Each treatment contained 3 replicates of 8 birds each. Average live body weight and feed consumption were recorded at 3 and 6 weeks of age. Body weight gain and feed conversion ratio were calculated during starting (0-3 weeks), growing (4-6 weeks) and the whole experimental period (0-6 weeks). At the end of the sixth week of age 3 birds were randomly taken from each treatment and slaughtered to measure carcass traits. The results revealed that, birds fed recommended diet had the best final body weight (6 weeks), Birds fed recommended diet had significantly higher body weight gain and feed consumption during the growing and whole experimental periods. Adding Nu3lease enzyme mixture to broiler diets significantly increased body weight and body weight gain and improved feed conversion ratio during staring, growing and whole experimental periods. Also, birds fed diet supplemented with Nu3lease enzyme had significantly higher dressing and giblets percentage and lower abdominal fat percentage. The best economical efficiency was recorded in chicks fed recommended diet supplemented with Nu3lease enzyme mixture