Objective: To investigate the clinical efficacy and safety analysis of bronchial thermoplasty (BT) in the treatment of severe asthma and asthma-chronic obstructive pulmonary disease overlap. Methods: The clinical data of 49 patients with asthma-COPD overlap who received BT in the University of Chinese Academy of Sciences Shenzhen Hospital from January 2016 to December 2018 and 50 patients with severe asthma who received BT in the same period were retrospectively analyzed. Patients were divided into overlap group and asthma group, and the baseline data of two groups were recorded. The pulmonary function before and after treatment (including forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), FEV1 as a percentage of predicted value (FEV1% pred)), hormone consumption, asthma control test (ACT) score, asthma quality of life questionnaire (AQLQ) score, asthma control questionnaire (ACQ) score, the overlap group before and after treatment COPD assessment test (CAT) score, modified British Medical Research Council (mMRC) score and postoperative respiratory adverse events in the next 3 weeks were comparatively analyzed. Results: The general baseline characteristics of the two groups are compared. The patients in the overlap group were older than those in the asthma group, and the course of disease and smoking history were longer than those in the asthma group. The inhaled hormone dosage in asthma group was greater than those in the overlap group ((64±11) years vs (48±11) years; 10.00 (10.00, 25.00) years vs 9.00 (1.75, 20.00) years; 20.00(2.00, 40.00) years vs 0 (0, 10.00) years; 320 (320, 640) μg/d vs 960 (320, 960) μg/d) (all P<0.05). The predicted values of lung function indexes FVC, FEV1, FEV1% pred in the overlap group before treatment were all lower than those in the asthma group (1.98 (1.43, 2.43) L vs 2.54 (2.02, 3.15) L; 0.92 (0.61, 1.26) L vs 1.69(1.17, 2.16) L; (50±16) L vs (65±14) L) (all P<0.05). There were no significant differences in ACT, ACQ, and AQLQ scores between the two groups before treatment (all P>0.05). Within 3 months after treatment, except for no significant improvement in FEV1% predicted value and inhaled hormone dosage in the overlap group (all P>0.05), other indexes in both groups were improved compared with those before treatment (all P<0.05). After 1 year of treatment, all indexes of the two groups were significantly improved than those before treatment, and all indexes of the asthma group were better than those of the overlap group (all P<0.05). In terms of respiratory adverse events occurring within 3 weeks after the operation, the incidence of cough and bloody sputum in the overlap group was higher than that in the asthma group, while the incidence of sputum and short-term wheezing was lower than that in the asthma group (all P<0.05). There were no statistically significant differences in the incidence of chest tightness, chest pain, segmental atelectasis and pneumonia between the two groups (all P>0.05), and the postoperative adverse reactions could be effectively controlled in a short period of time. Conclusion: BT treatment could not only improve the lung function, clinical symptoms and quality of life of asthmatic patients, but was also effective for asthma-COPD overlap patients. However, BT treatment had more benefits for asthmatic patients without serious adverse events occurred.