Objective：To observe the curative effect of Jiedu Huoxue yin combined with simvastatin tablets for carotid atherosclerosis.Methods：Divided 90 patients with carotid atherosclerotic plaque with phlegm-stasis in channels into the control group and the observation group randomly，45 cases in each group.Both groups received simvastatin tablets orally，while the observation group was additionally given oral administration of Jiedu Huoxue yin.Both groups continuously received treatment for 3 courses，4 weeks being one course.Detected carotid intima-media thickness(IMT)，plaque area，and blood flow parameters[end diastolic velocity(EDV)，peak systolic velocity(PSV)，pulsation index(PI)and resistance index(RI)].Results：After treatment，IMT and plaque area in two groups were both decreased when compared with those before treatment(P＜0.05)，and EDV and PSV in two groups were both increased when compared with those before treatment(P ＜ 0.05).Compared PT and RI in two groups with those before treatment，there were no significant differences being found(P ＞ 0.05).IMT and plaque area of the observation group were both better than those of the control group(P ＜ 0.05)，and EDV and PSV of the observation group were both higher than those of the control group(P＜0.05).Conclusion：The additional application of Jiedu Huoxue yin based on simvastatin tablets therapy can help reducing IMT，the size of atherosclerotic plaque，increasing blood flow velocity in the common carotid artery，and improving atherosclerosis.