Objective: To investigate the effects of a mobile health smartphone application to support self-management programmes on quality of life, self-management behaviour and exercise and smoking cessation behaviour in patients with chronic obstructive pulmonary disease (COPD). Design: A randomised controlled, single-blind trial, was carried out from November 2017 to February 2019, which included 78 participants admitted with COPD to the Affiliated Hospital of Zunyi Medical University in Guizhou. The study participants were randomised into intervention ( n = 39) and control groups ( n = 39). Methods: Participants in the intervention group undertook a mobile medical application-based programme in addition to routine care, and participants in the control group received only routine care. The outcome measures were health-related quality of life evaluated by the COPD Assessment-Test, self-management behaviour using the COPD Self-Management Scale and physical activity and smoking behaviour were measured using a self-designed questionnaire. Data collection was conducted at baseline, third month, sixth month and 12th months. Results: Thirty-five participants in the intervention group and 33 in the control group completed the study. Compared to the control group, participants in the intervention group showed statistically significant improvement in the COPD -Assessment -Test scores ( P < 0.01) and in all domains of the COPD Self-Management Scale scores ( P < 0.01) at 12th 12 months. Improvements in the COPD -Assessment -Test scores by 4.3 and 0.3 units, and in the total scores of the COPD Self-Management Scale total score by 23.01 and 2.28 units, respectively, were observed in the intervention and control groups, respectively over the 12-month study period. Meanwhile, the mobile health application programme also improved participants’ exercise and smoking cessation behaviour. Conclusions: The mobile health smartphone application to support self-management programmes was effective in improving health-related quality of life and self-management behaviour in patients with COPD. Trial registration: This study was registered in Chinese clinicaltrials.gov