Objective To investigate the effects of mask BiPAP noninvasive positive ventilation (NIPPV) during treadmill exercise on dyspnea index and exercise endurance in stable patients with severe chronic obstructive pulmonary disease (COPD). Methods Twenty inpatients with stable severe COPD between August 2015 and January 2016 were recruited in the study. The following parameters were measured before and after 8-week rehabilitation by NIPPV during treadmill exercises, including 12-minute walking distance (12MWD), Borg dyspnea score, mean pulmonary arterial pressure (mPAP), PaO 2 and PaCO 2, times of acute exacerbation in 1 year, adverse reactions, and adherence. Results After rehabilitation for 8 weeks, the following parameters were improved than those before treatment including 12MWD [(810±20) mvs. (680±15) m,P<0.01], Borg dyspnea score (2.4±0.1vs. 4.4±0.3,P<0.01), mPAP [(34.4±2.7) mm Hgvs. (43.5±3.8) mm Hg], PaCO 2 [(49.8±4.9) mm Hgvs. (64.3±5.2) mm Hg], PaO 2 [(64.4±4.1) mm Hgvs. (52.3±3.9) mm Hg] and the times of acute exacerbation (2.1±0.7vs. 4.3±2.1,P<0.01). Adverse reactions included oropharyngeal drying (2 cases) and gaseous distention (8 cases) which can be tolerated without special treatment. Conclusion Mask NIPPV during treadmill exercise is safe and effective for stable patients with severe COPD and worthy of clinical application.