Panax notoginseng exhibit several beneficial effects including anti-oxidant effects. P. notoginseng is used as a therapeutic agent to stop haemorrhages and a tonic to promoted health in Korean and Chinese medicine. The pharmacokinetic profiles of the main P. notoginseng are still not accurately investigated. The exact mechanism of the anti-oxidant activitys of water extracts of P. notoginseng, however, has not been determined. in present study, I examined the effects of water extracts of P. notoginseng on high cholesterol diet atherosclerosis-induced rats in serum and abdominal aorta. A total of 3-week old 9 male rats of Sprague-Dawley were divided into 3 groups and fed with the basal diet (normal group), high cholesterol diet (atherosclerosis induced group) for 8 weeks, high cholesterol diet supplemented with water extracts of P. notoginseng (P. notoginseng group) for 4 weeks. And rats were sacrificed, serum lipid level, abodominal aortic anti-oxidant activities and lipid peroxide were measured. These results indicated that serum total cholesterl, LDL-cholesterol, triglycerides concentration significently lowered in P. notoginseng group than high cholesterol diet group. But HDL-cholesterol concentraion significently higher in P. notoginseng group than high cholesterol feed group. And abdominal aortic xanthine oxidase activity was significantly reduced by dietary water extracts of P. notoginseng supplementation (p<0.05) Also abdominal aortic superoxide dismutase, catalase, glutathione peroxidase activities were significantly increased by dietary water extracts of P. notoginseng supplementation (p<0.05) Especially, abdominal aortic level of lipid peroxide tended to increase in high cholesterol feed group, but water extract of P. notoginseng intake reduced the value (p<0.05).