Objective To analyze the therapeutic effect of noninvasive mechanical ventilation in chronic obstructive pulmonary disease (COPD) patients with respiratory failure.Methods Sixty patients with COPD respiratory failure were randomly divided into two groups.30 cases in the conventional treatment group used conventional comprehensive therapy.30 cases in the nonfinvasive mechanical ventilation group were given noninvasive mechanical ventilation based on conventional treatment.The total effective rate,time to correct the abnormal breathing,hospitalization time were compared between the two groups.Before and after treatment,the arterial blood gas analysis indicators and heart rate,respiratory rate,probability,mortality for ventilator ventilation were compared in the two groups.Results The total effective rate of the noninvasive mechanical ventilation group was 96.67％,which was higher than 73.33％ of the conventional treatment group(x2 =6.405,P ＜ 0.05).The time to correct the abnormal breathing,hospitalization time of noninvasive mechanical ventilation group were (5.51 ± 1.41) d,(9.51 ± 2.13) d,respectively,which were shorter than (9.39 ± 2.56) d,(12.99 ± 3.57) d of the conventional treatment group (t =8.223,9.633,all P ＜ 0.05).Before treatment,the arterial blood gas analysis parameters and heart rate had no statistically significant differences between the two groups (all P ＞ 0.05).After treatment,the frequency of PaCO2,PaO2,heart rate and respiratory rate in the conventional treatment group were (60.45 ± 3.94)mmHg,(60.24 ± 4.12)mmHg,(92.58 ± 0.61)times/min,(22.45 ± 3.14)times/min,respectively,which in the noninvasive mechanical ventilation group were (52.24 ± 1.23) mmHg,(76.24 ± 5.26) mmHg,(83.92 ± 0.62) times/min,(17.26 ± 2.23) times/min,respectively,the differences between the two groups were statistically significant(t =5.133,3.734,5.166,6.360,all P ＜ 0.05).The invasive rate of invasive ventilator and mortality of noninvasive mechanical ventilation group were 3.33％ and 0.00％,respectively,which were lower than 20.00％,13.33％ of the conventional treatment group (x2 =7.214,6.247,all P ＜ 0.05).Conclusion Noninvasive mechanical ventilation is effective in treatment of patients with COPD respiratory failure,which can effectively improve the indicators of arterial blood gas and heart rate and respiratory rate,improve the prognosis of patients,improve the ventilation probability of invasive ventilator.