AIM:To find a new way of treating premature beats(PB) to evaluate the efficacy and safety of Yi-(xinshu) Capsule(Radix et Rhizoma Ginseng,Radix et Rhizoma Salviae miltiorrhizae,Radix Ophiopogonis,Radix Astragali,etc.) METHODS:Randomized,controlled clinical study were conducted in 60 patients with atrial premature beats(APB),and 60 patients with premature ventricular beats(PVB).APB patients were randomly divided into two groups:Yixinshu Capsule plus Isoptin(study group,n=30) and Isoptin group(control group,n=30).PVB patients:Yixinshu Capsule plus Mexiletine(study group,n=30) and Mexiletine group(control group,n=30).Those patients were treated for four weeks.We used 24 h Holter to monitor the times of PB and myocardial ischemia in before and after treatment.RESULTS:In the study group and control group,the times of APB and PVB were decreased obviously after 4 weeks treatment(P