Liver cirrhosis was induced in rats by the combined action of oral phenobarbitone and inhalations of carbon tetrachloride vapors. These rats manifested hepatosplenomegaly, hypoalbuminemia, and 2- to 17-fold elevations in serum transaminases and alkaline phosphatase levels. The hepatic antioxidant enzymes, superoxide dismutase and catalase, showed 28 and 60% decreases, respectively. There was, however, no increase in the hepatic lipid peroxidation. These studies suggest that in cirrhosis liver cell damage may result due to the direct attack of the oxygen free radicals. Lipid peroxidation in the liver may not be a prerequisite for the development of cirrhosis, as is generally believed.