the aim of this study was to evaluate the inclusion of an enzimatic complex in diets for nile tilapia (oreochromis niloticus) on performance, carcass chemical composition as well as water quality. the experiment was performed in 62 days. it was used two hundred reverted fingerlings (14.57 ± 1.24 g) distributed in a complete randomized design in 20 500 l-tanks with four treatments and five replicates, considering a box with 10 fish as a experimental unit. the fish were fed diets containing 0; 0.033; 0.066 and 0.099% of enzimatic complex. the diets were processed in peletized way and supplied four times a day (8:00 a.m., 11:00 a.m., 2:00 p.m. and 5:00 p.m.) the ph average values, electric conductivity, dissolved oxygen, temperature, total phosphorus, ammonia and water nitrate of the cultivation were not influenced by the inclusion of the enzimatic complexin the diet. the inclusion of enzymatic complex in the diet did not affect weight gain, survival, and specific growing rate; however, it affected diet consumption and food conversion, whose values were greater for fish fed 0.066% of enzimatic complex diet. no differences were observed on dry matter, humidity, crude protein, mineral matter, calcium and phosphorus in the fish carcass, nevertheless, the ether extract decreased linearly as the level of enzymatic complex increased. the utilization of enzimatic complex (amylase, protease, cellulase, lipase, pectinase, xylanase, β-glucanase and phytase) at the level of 0.066% for juvenile nile tilapia (oreochromis niloticus) worsens food conversion but does not influence performance and body composition of the fish.