Abstract: Objective: To observe the curative effect of Pingxin Fumai mixture combined with metoprolol succinate sustained-release tablets on frequent premature ventricular contractions and its effect on the heart rate variability. Methods: A total of 80 cases of patients with frequent premature ventricular contractions of qi- yin deficiency type were enrolled and divided into the treatment group and the control group according to the random number table method,40 cases in each group. The control group was given metoprolol succinate sustained-release tablets,and the treatment group was additionally given Pingxin Fumai mixture based on the treatment of the control group. Both groups were treated for four weeks. The indexes of the heart rate variability before and after treatment,clinical effect,and the incidence of adverse reactions were compared between the two groups. Results:The total effective rate was 90.0% in the treatment group,and 72.5% in the control group,the difference being significant(P<0.05). Before treatment,there was no significance in the difference being found in the comparison of indexes of the heart rate variability between the two groups(P>0.05). After treatment, the standard deviation of normal-to-normal intervals(SDNN),root mean square of successive differences of normal-to-normal intervals(rMSSD),and high frequency(HF) in the two groups were increased when compared with those before treatment(P< 0.05), and low frequency(LF) was decreased when compared with that before treatment(P<0.05). After treatment,SDNN, rMSSD and HF in the treatment group were larger than those in the control group,and LF was smaller than that in the control group(P<0.05). The incidence of adverse reactions was 2.50% in the two groups, there being no significance in the difference between the two groups(P>0.05). Conclusion:In the treatment of frequent premature ventricular contractions, the therapy of Pingxin Fumai mixture combined with metoprolol succinate sustained- release tablets can improve the heart rate variability with safety and effectiveness.