Objective:To observe the curative effect of noninvasive positive pressure ventilation (NIPPV) in the treatment of severe COPD-induced type II respiratory failure combined with acute left heart dysfunction. Methods:Eighty-six COPD patients with acute left heart dysfunction were randomly divided into control group (n = 43) and treatment group (n = 43). The control group was treated with routine treatment,and the treatment group was treated with bi-level positive airway pressure (BiPAP) ventilation through a nasal or face mask in addition to routine treatment. For the treatment group,continuous BiPAP ventilation was given in the first 2 days. Since the third day,the patients were given 8 to 20 hours BiPAP ventilation. BiPAP ventilation was gradually weaned when patient＇s condition stabilized. Changes of heart rate,blood gas indexes,left ventricular ejection fraction (LVEF),NT-proBNP,and clinical symptoms (including dyspnea,conscious state,pulmonary rales) in the two groups before and after the treatment were compared. Results:The heart rate,pH,PaO2,PaCO2 in the treatment group after BiPAP ventilation for 2 h,24 h,48 h,and 7 d were significantly improved compared to those of the control group (all P < 0.05). The LVEF values of 7 days after BiPAP ventilation in the treatment group were significantly increased than that of the control group. Moreover,the NT-proBNP levels of the treatment group were significantly decreased compared to the control group after 48 hours and 7 days treatment. Conclusion:BiPAP ventilation had a good therapeutic effect for patients with severe COPD-induced type II respiratory failure combined with acute left heart dysfunction.