Abstract: Objective: To evaluate the clinical effect of non invasive,binary level positive airway pressure(BiPAP) ventilation respirator in treatment of chronic obstructive pulmonary disease(COPD) accompanied by type Ⅱ respiratory failure.Methods: Fifty-seven cases of COPD were randomly divided into two groups(28 cases in control group and 29 cases in treatment group).The control group were treated with routine therapy only and the treatment group received non-invasive positive pressure ventilation(NPPV) with BiPAP ventilator in addition to the routine therapy.The heart rate(HR),respiratory rate(RR) and parameters of gas exchange were measured in each group at the time of enrollment(0 hour),24 hours and 48 hours after treatment.Results: Compared with the control group,the HR,RR and arterial blood gas in the treatment group were significantly improved after ventilation for 24 h and 48 h.The difference was significant(P<0.01).After the therapy,the foregoing parameters in the treatment group were superior to the control group(P<0.05-P<0.01) and no obvious side effect was observed.Conclusions: NPPV has a remarkable healing effect on chronic obstructive pulmonary disease combined with typeⅡrespiratory failure and has great practical value in clinical application.