OBJECTIVE To evaluate the efficacy and safety of Chinese medicinal shensongyangxin capsules in the treatment of paroxysmal atrial fibrillation. METHODS From August 2007 to July 2008, Beijing Chaoyang Hospital conducted a multicenter study, select the eleven hospital's outpatient subjects, aged 18 to 75 years old, male or female, paroxysmal atrial fibrillation (at least one electrocardiogram diagnosis) seizure frequency ≥ 2 times/month, according to the ratio 1:1:1, subjects were randomly divided into three groups: a. shensongyangxin group, taking shensongyangxin capsule 4 + propafenone analogues 150 mg, 3 times a day; b. propafenone group, taking propafenone tablets 150 mg + 4 shensongyangxin analogues, 3 times a day; shensongyangxin capsule + propafenone group, taking shensongyangxin capsule 4 + propafenone 150 mg, 3 times a day. The treatment course is 8 weeks, with 3 times of follow-up. RESULTS Total of 349 cases of paroxysmal atrial fibrillation, which 117 cases in shensongyangxin group, 115 cases in propafenone group; 117 cases in shensongyangxin + propafenone group. The baseline data analysis showed that there were no significantly difference (P > 0.05) among the three groups of atrial fibrillation seizure frequency, vital signs, general condition, medical history, 24-hour ambulatory ECG, 12-lead normal electrocardiogram, cardiac ultrasound and symptoms. The comparison before and after (8 weeks) treatment showed that the frequency (from 6 times/m to 2 times/m in each group, P < 0.01), number of cases [from 46 (43.3%) to 22 (20.8%), 43 (43.4%) to 25 (25.3%), and 40 (40.6%) to 31 (29.2%), respectively P < 0.01] and duration time of attack of atrial fibrillation (from 4 h to 0.5 h, 4 h to 0.5 h, and 4.25 h to 0.5 h, respectively P < 0.01) all decreased in three groups. No significant difference among the three groups comparing the overall effect (62.3%, 58.6%, and 58.5%, respectively, P > 0.05), while the efficacy of TCM symptoms in shensongyangxin group (80.2%) was better than that of propafenone group (67.7%) (P < 0.05). Safety evaluation showed that adverse reaction rate was 1.8% in shensongyangxin group, and 8.2% and 5.4% in propafenone group and shensongyangxin + propafenone group. CONCLUSIONS Shensongyangxin capsules and propafenone have comparable efficacies in the treatment of PAF. The efficacy of TCM symptoms is better than propafenone. Shensongyangxin capsules have an excellent profile of safety.