Lipid peroxidation is one of the main manifestations of oxidative damage and has been found play an important role in the toxicity and carcinogenesis of many carcinogens. This study was carried out to investigate the effects of aflatoxin B₁ co-administrated with antioxidant vitamins on lipid contents and fatty acids components of liver in mice. For this work, vitamin C and vitamin E, the major antioxidants, were administrated with 10 ㎎/㎏ and 63.8 ㎎/㎏ respectively, through intraperitoneal(i.p) injection to male ICR mice, and 0.4 ㎎/㎏ of the AFB₁ injected by i.p. lhr later. The results were as follows: two fold amounts of free cholesterol, triglyceride, and total cholesterol in serum and liver of mice treated with only AFB₁ were observed, when compared to those of mice co-administrated with antioxidant vitamins. However, the levels of phospholipids in serum and liver of mice treated with only AFB₁ were decreased. Concerning to fatty acids composition of liver from AFB₁-treated mice, P/S ratio was shown more low level in cholesteryl ester, triglyceride, total cholesterol and phospholipid than those of mice co-administrated with antioxidant vitamins. In these data which provide with a reliable evidence on their antioxidantal effects to aflatoxicosis.