Rats were given aflatoxin B1 (7.5 microg/200 g b.w.) and alpha-tocopherol (0.9 mg/200 g b.w.) for 14 days oral intubation to investigate the effect of alpha-tocopherol on the toxicity of aflatoxin B1 on rat's testes. There were significant alterations in testicular sorbitol dehydrogenase, lactic dehydrogenase, glucose-6-phosphate dehydrogenase, gamma glutamyl transpeptidase; reduced quality of sperm and marked pathological changes in the testis of rats given aflatoxin B1 alone. Alpha-tocopherol supplementation increased the aflatoxin blood level. A reduction in the toxicity of free radicals by alpha-tocopherol in association with a reduction in aflatoxin metabolism seem to be responsible for the protective influence observed.