Abstract： Objective To study the clinical effects and safety of metoprolol for chronic heart failure(CHF). Methods One hundred and thirty patients with CHF(cardiac function NYHA Ⅱ-Ⅳclass)were divided randomly into two groups: treatment group(66 cases) was added with small dose metoprolol. Observatin, indexes included heart rate,systolic blood pressure(SBP),diastolic blood pressure(DBP),heart functional class,left ventricular end-diastolic diameter(LVEDD) and left ventricular ejection fraction(LVEF) . Results After treatment,the observation indexes in both groups were improved significantly. The improvement in treatment group was better than the control group(P<0.05). Conclusion Metoprolol at a small dose is an effective and safe medicine for patients with CHF.