Our aim is to investigate the efficacy of continuous positive airway pressure (CPAP) in chronic obstructive pulmonary disease (COPD) combined with respiratory failure. Electronic and manual searches were applied to retrieve published studies relevant to CPAP, COPD, and respiratory failure. The retrieved studies were screened based on stringent inclusion and exclusion criteria to identify high-quality clinical studies for meta-analysis. Comprehensive meta-analysis 2.0 was conducted to statistical analysis. Initially, we retrieved 958 studies based on stringent inclusion and exclusion criteria, 10 studies, containing a total of 372 patients with COPD combined with respiratory failure, were selected for meta-analysis. The result of our meta-analysis revealed that partial pressure of carbon dioxide (PaCO2) in patients with COPD combined with respiratory failure was significantly lower 24 hours after CPAP treatment, and partial pressure of oxygen (PaO2) and pH were markedly higher 24 hours after CPAP treatment in the same patient group, indicating statistically significant differences as a result of CPAP treatment. Subgroup analysis based on ethnicity demonstrated that PaCO2 in patients with COPD combined with respiratory failure is evidently lower 24 hours after CPAP treatment among whites, but no such statistical correlation was observed among Asians. The results of this meta-analysis indicate that CPAP can effectively improve the respiratory function of patients with COPD combined with respiratory failure, and CPAP can be an effective way of treating COPD.