Objective To observe the effect of Bi-level positive airway pressure(BiPAP) noninvasive ventilation on acute left ventricular failure(LVF). Methods BiPAP group :32 patients with severe LVF from various causes were treated by BiPAP with traditional drugs. Control group:32 patients were treated with traditional drugs alone,and the results were compared with those of BiPAP group. Results Dyspnea was relieved in all patients in BiPAP group,both the respiratory rate and heart rate were slowed,the vital signs were stable,and PaO2 ,SaO2 went up. The total effective rate was 100%, which was only 68. 75% in control group. Conclusion The use of BiPAP noninvasive ventilation therapy is feasible and effective on LVF.