Objective To oberserve effect of Yiqi Tongmai Decoction for vascular endothelial function in patients of unstable angina pectoris of coronary heart disease. Methods 125 patients with unstable angina pectoris treated in our hospital were randomly divided into 65 cases in the observation group and 60 in the control group. The patients in the control group were treated with conventional western medicine， and the observation group was treated with Yiqi Tongmai Decoction on the basis of the control group. The changes of cardiac function， myocardial reperfusion injury and vascular endothelial function index before and after treatment were compared between the two groups. Results After treatment， the frequency of angina pectoris and the duration of angina were significantly decreased in the 2 groups（P<0.05）， and the degree of reduction in the observation group was significantly higher than that of the control group（P<0.05）. After treatment， the indexes of cardiac function of the 2 groups were obviously improved（P<0.05）， and the improvement of the observation group was obviously better than the control group（P<0.05）. After treatment， the level of NO in the 2 groups was significantly higher than before treatment， and the level of ET-1 was significantly lower than before treatment（P<0.05）， and the degree of change of the observation group was significantly better than the control group（P<0.05）. Conclusion Yiqi Tongmai Decoction combined with routine treatment can effectively improve the clinical symptoms of unstable angina pectoris patients， and effectively improve cardiac function and endothelial function of patients， which is worthy of clinical application.