Abstract: An investigation was made on the performance of 144 unsexed Van Cobb broiler chicks from 21 days to 42 days of age. The chicks were fed on soybean meal (SM) based iso-nitrogenous and iso-energetic diet incorporating phytase with the levels of 0.0, 0.50, 1.00 and 1.50 g/kg diet for better utilization of the basal diet. The growth rate, feed intake, feed consumption, dressing yield and profitability increased as the level of phytase supplementation increased and the level of phytase had no effect on survivability. The addition of phytase seemed to be effective to overcome the antinutritive effect of phytate phosphorus and non-starch polysaccharides (NSP) on broiler performance. Therefore, it was concluded that 1.50 g/kg phytase may be incorporated in SM based broiler diet for profitable production.