A dose, 1g/kg of ethanol produced experimental hyperuricemia in mouse. Ginseng saponins were tested for their ability to alter the hepatic xanthine oxidase activity and the blood level of uric acid in the ethanol-treated mouse. Intraperitoneal injection of ginseng saponin 4mg/kg markedly decreased the xanthine oxidase activity in the ethanol-treated mouse liver. It was also observed that ginseng saponin reduced the blood concentration of uric acid in experimentally induced hyperuricemia by alcohol treatment. In vitro, it was found that a low concentration of ginseng saponin in the reaction mixture incresed the hepatic xanthine oxidase activity, while a high concentration inhibited both enzyme preparations of normal and ethanol treated mice. In contrast with the xanthine oxidase, uricase activity was not influenced by ginseng saponin as well as in vivo. These results suggest there is a possibility that ginseng saponin may have some therapeutic effect on gout and other hyperuricemia syndrome.