ObjectiveTo assess the mortality, acute exacerbations, exercise capacity, symptoms and significant physiological parameters (lung function, respiratory muscle function and gas exchange) of patients with severe stable chronic obstructive pulmonary disease (COPD) with respiratory failure treated by noninvasive positive pressure ventilation (NPPV).MethodsA meta-analysis of randomized controlled trials was carried out by searching PubMed, Cochrane library, Embase, OVID, Chinese Biomedical Literature Database and the bibliographies of the retrieved articles up to February 2017. Studies of patients with severe stable COPD with respiratory failure receiving long-term noninvasive positive pressure ventilation and comparison with oxygen therapy were conducted, and at least one of the following parameters were reviewed: frequency of acute exacerbations, mortality, lung function, respiratory muscle function, gas exchange, 6-minute walk test.ResultsSix studies with 695 subjects met the inclusion criteria and were analyzed. The PaCO2 was significantly decreased in patients who received long-term NPPV. No significant difference was found between long-term NPPV and oxygen therapy in mortality, frequency of acute exacerbations, gas exchange, lung function, respiratory muscle function and exercise capacity. The subgroup analysis showed that NPPV improves survival of patients when it is targeted at greatly reducing hypercapnia.ConclusionCurrent evidence suggests that there is no significant improvement by application of NPPV on severe stable COPD with respiratory failure patients, but NPPV may reduce patients’ mortality with the aim of reducing hypercapnia.