Effects of Panax ginseng on plasma and hepatic lipids were investigated in the high cholesterol diet-fed rats and in patients with hyperlipidemia. Oral administration of red ginseng powder reduced plasma total cholesterol, triglyceride and NEFA, while plasma HDL-cholesterol was elevated. Platelet adhesiveness was also reduced by ginseng administration. The plasma lipid-improving actions were also observed in patients with hyperlipidemia. Hepatic cholesterol and triglyceride contents were decreased and phospholipid increased by ginseng administration in the high cholesterol diet-fed rats, corresponding to improvement of the fatty liver.