Abstract： Objective： To observe the clinical effect of Mazhu No. 2 Prescription combined with Aminophylline for sinus bradycardia of yang deficiency type. Methods：A total of 58 cases of patients with sinus bradycardia of yang deficiency type were selected and divided into the observation group and the control group according to the random number table method， with 29 cases in each group. The control group was treated with Aminophylline Tablets orally， and the observation group was additionally treated with Mazhu No.2 Prescription based on the treatment of the control group. The treatment course lasted for two weeks. Clinical effects， traditional Chinese medicine (TCM) syndrome scores， 24-hour dynamic electrocardiogram (mean heart rate， lowest heart rate， highest heart rate， and total heart rate)， and adverse reactions were compared between the two groups. Results：The total effective rate was 96.55% in the observation group， which was higher than that of 79.31% in the control group (P＜0.05). After treatment， TCM syndrome scores in the two groups were reduced when compared with those before treatment (P＜0.05)， and the scores in the observation group were lower than those in the control group (P＜0.05). After treatment，the mean heart rate，lowest heart rate，highest heart rate，and total heart rate in the two groups were increased when compared with those before treatment (P＜0.05)， and the mean heart rate，lowest heart rate，highest heart rate，and total heart rate in the observation group were higher than those in the control group (P＜0.05). The incidence of adverse reactions was 6.90% in the obsertation group， which was lower than that of 27.58% in the control group (P＜0.05). Conclusion： Mazhu No. 2 Prescription combined with Aminophylline has a definite curative effect in the treatment of sinus bradycardia of yang deficiency type， which can improve clinical symptoms of patients and promote the recovery of 24-hour electrocardiogram monitoring results，with high medication safety.