Abstract：Objective：To observe the effect of Tongxinluo capsules combined with metoprolol on QT dispersion，vascular endothelial function and heart rate turbulence(HRT) in patients with coronary heart disease complicated with ventricular premature beats. Methods： A total of 164 cases of patients with coronary heart disease complicated with ventricular premature beats were selected and divided into the observation group and the control group according to the random number table method，with 82 cases in each group. The control group was given the oral administration of metoprolol tartrate tablets， and the observation group was additionally given Tongxinluo capsules based on the treatment of the control group. Both groups were treated for four weeks. Clinical effects and the effects of ventricular premature beats in the two groups were observed. The changes of 24- hour ambulatory electrocardiogram， serum [endothelin- 1(ET- 1)， thromboxane B2(TXB2)， nitric oxide(NO)] and HRT parameters [turbulence onset(TO) and turbulence slope(TS)] were compared between the two groups before and after treatment，and the incidence of adverse reactions during treatment was observed. Results：The total effective rate was 80.5% in the control group and 93.9% in the observation group，the difference being significant(P＜0.05). From the perspective of ventricular premature beats，the total effective rate was 75.6% in the control group and 89.0% in the observation group，the difference being significant(P＜0.05). After four-week treatment，PR interval in the electrocardiogram indexes in the two groups was reduced when compared with that before treatment，and the QRS wave duration and QTc interval were increased， differences being significant(P＜0.05)； PR interval in the electrocardiogram indexes in the observation group was shorter than that in the control group， and the QRS wave duration and QTc interval were longer， differences being significant(P＜0.05). After treatment，NO levels in serum in the two groups were increased when compared with those before treatment， and there was significant difference being found in the comparison of NO level in the observation group before and after treatment(P＜0.05)；levels of ET-1 and TXB2 were decreased when compared with those before treatment， differences being significant(P＜0.05)； NO level in the observation group was higher than that in the control group，levels of ET-1 and TXB-2 were lower than those in the control group，differences being significant(P＜0.05). After treatment，TO and TS in the two groups were improved，differences being significant(P＜0.05)；the improvement of TO and TS in the observation group was better than that in the control group，the difference being significant(P＜0.05). The liver and kidney functions in the two groups were normal during administration and no other obvious adverse reactions were found. Conclusion：Tongxinluo capsules combined with metoprolol has an obvious curative effect in the treatment of coronary heart disease complicated with ventricular premature beats. It can reduce QT dispersion and inhibit the occurrence of malignant arrhythmia.