The antioxidants, biochemical, and mutagenic effects of butylated hydroxytoluene (BHT) in doses of 3 and 30 mg/kg b.wt. were studied in normal and CC14-intoxicated rats. The oral LD59 of BHT in rats was 1740 mg/kg b.wt. No significant changes of almost all of the studied serum and tissue parameters including bone marrow cells compared to the control groups indicating the safety of this compound. CCI4- intoxicated animals showed significant elevations in serum alanine aminotransferases (ALT), aspartate aminotransferases (AST) and alkaline phosphatase (AP) activities. serum bilirubin, cholesterol, creatinine, urea and tissue lipid peroxides (LP) concentrations. In contrast, significant reduction was observed in tissue reduced glutathione concentration (GSH). Oral administration of BHT concurrently with CCl4 for 4 weeks significantly returned all the biochemical parameters to toward their normal values confirming safety and excellent antioxidant effect of BHT.