Aim: To study the mechanism of naoluotong on anti-atherosclerosis in quails.Methods: After the atherosclerosis (As) model in hyperlipemia quails were made,we measured the total cholesterol (TC ) and triglyceride (TG ) in serum, prostacyclin (PGI2 ) and thromboxane A2 (TXA2 ) in plasma, lipid peroxidation (LPO) and superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px)in brain tissuse. we estimated the grade of As by given points.Results: Naoluotong have no effects of reducing the amount of TC and TG, but increasing the amount of SOD (P<0. 05) and alleviating the formation of As plaque (P<0.05).Conclusion: The mechanism of naoluotong on inhibiting the formation of As plaque is not reducing hyperlipermia but antioxidation.