Introduction: Although the benefit of non-invasive mechanical ventilation (NIMV) has been proven in the management of acute exacerbations of chronic obstructive pulmonary disease (COPD), the data are limited for other lung conditions, including pneumonia and bronchiectasis.In this study, we aimed to investigate the success of NIMV in COPD patients with acute hypercapnic respiratory failure (AHRF) and concomitant pneumonia or bronchiectasis.Methods: Among the patients hospitalized in the intensive care unit (ICU) due to AHRF, 62 patients suitable for NIMV application were included in the study.The patients were divided into three groups: Group 1: COPD (n=34), Group 2: COPD + bronchiectasis (n=11), and Group 3: COPD + pneumonia (n=17).We evaluated the success of NIMV among those 3 groups.Results: Three study groups were similar for NIMV success, length of stay in ICU, and mortality.Discussion and Conclusion: There is increasing evidence for the benefit of NIMV in the management of AHRF.Although the use of NIMV in COPD exacerbations has been strongly recommended by many randomized controlled trials, more studies are needed to prove its benefit in patients with pneumonia and bronchiectasis.