This study was done to investigate the toxic effects of aflatoxin B1(AFB1) on Nile tilapia(Oreochromis niloticus) fingerlings and detoxifying these drastic effects by using some antimycotoxins. Therefore, 0.5 and 1g of each Black pepper, Filofeed plus and Cap T 2 were added to an aflatoxin diet (150ppb) for fingerlings. These diets were offered 6 days a week at 3% daily of actual biomass in glass aquaria (three aquaria / treatment) in the wet Lab. The experiment lasted for 14 weeks (98 days). The Aflatoxic diet had adversely affected growth performance, survival rate, feed and protein utilization, muscular and abdominal areas and carcass composition of fish as well as residues of AFB1 (ppb) was observed in the viscera and muscles of fish. The addition of antitoxins alleviated aflatoxicosis of fish, moreover, it improved all the above tested parameters. Generally, the results obtained of this study recommended that adding 0.5 or 1g of Black pepper, Filofeed plus and Cap T2 as fish feed additives could be used as detoxifying agents for aflatoxin.