Effects of acanthopanax cortex extracts on glutathion S-transferase (GST), glutathion peroxidase (GSH-px) and superoxide dismutase (SOD) activities related to 7,12-dimethyl-benz(a)anthracene(DMBA) metabolism and on DMBA-induced mutagenicity were investigated in this study. From the comparative study of three extracts, it was found that butanol extract was more potent than other extracts in increment of GST, GSH-px and SOD activities and in inhibitory effects of lipoperoxide formation of liver. Also ether and butanol extracts inhibited DMBA-induced mutagenicity, showing 33% to 36% of inhibition at maximum, when ether and butanol extracts were administered to rats intraperitoneally.