This study was conducted in order to investigate the effects of Acer tegmentosum Maxim. extract (ATE) in prevention of liver injury. After oral administration of ATE to SD rats, liver injuries were induced by treatment with CCl₄, galactosamine, or ethionine. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), triglyceride, and cholesterols in blood were used as indicators of liver damage. When acute hepatitis was induced by CCl₄ or galactosamine, ATE-fed rats showed a lower level of AST and ALT in plasma than ATE-unfed rats. In the case of ethionine-induced fatty liver, triglyceride levels in plasma were reduced in ATE-fed rats, compared with ATE-unfed rats. These results indicate that Acer tegmentosum Maxim. extract protected against hepatic failure.