Magnolia obovata exhibit several beneficial effects including anti-oxidant effects. Magnolia obovata is used as a therapeutic agent to stop hemorrhages and a tonic to promoted health in Korean and Chinese medicine. The pharmacokinetic profiles of the main Magnolia obovata is still not accurately investigated. In present study, I examined the effects of water extracts of Magnolia obovata on atherosclerosis induced high cholesterol diet in 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 Magnolia obovata (Magnolia obovata group) for 2 weeks. And rats were sacrificed, serum lipid level, abodominal aortic anti-oxidant activities and lipid peroxide were measured. These results indicated that serum total cholesterol, LDL-cholesterol, triglycerides concentration significantly lower in Magnolia obovata group than high cholesterol diet group. But HDL-cholesterol concentration had significantly higher in Magnolia obovata group than high cholesterol diet group. In conclusion, Magnolia obovata controls of lipid level of hyperlipidemia and hypercholesterolemia, thus suppresses the proliferation of intima in endothelial cells, which is risk factors of atherosclerosis induced high cholesterol diet in rats. I consider as Magnolia obovata is worth to using as atherosclerosis treatment.