Objective: To investigate the effect of extracorporeal diaphragmatic pacing combined with aerobic breathing exercise on diaphragmatic function and pulmonary rehabilitation in the stroke patients with hemiplegia. Methods The study was conducted in 65 patients [age (73.90±3.81) years] with hemiplegia after stroke in the Fourth Rehabilitation Hospital of Shanghai from May 2019 to April 2020. According to using diaphragmatic pacing or not, the patients were divided into aerobic breathing exercise group (control group, n=31) and aerobic breathing exercise + diaphragmatic pacing treatment group (intervention group, n=34). Before and after a 12-week-treatment, the pulmonary function and diaphragmatic ultrasound were used to evaluate all patients, and the difference of parameters before and after treatment in the group and between groups was compared. Results After treatment, the indexes including pulmonary function parameters, diaphragm thickness [(0.22±0.01) cm vs. (0.20±0.02) cm], diaphragmatic calm activity [(1.44±0.13) cm vs. (1.31±0.96) cm], maximum diaphragmatic activity [(3.98±0.49) cm vs. (3.23±0.35) cm] were all significantly improved in the aerobic breathing exercise + diaphragm pacing group (all P<0.001). The forced expiratory volume in one second (FEV₁), FEV₁/forced vital capacity (FVC) and diaphragmatic activity in the control group were significantly improved (all P<0.005), while the FVC and diaphragm thickness didn’t show statistical difference(P>0.05). The pulmonary function parameters and diaphragmatic function evaluation in the intervention group were significantly ameliorated than those in the control group (all P<0.05). Conclusions The external diaphragmatic pacing combined with aerobic breathing exercise can significantly improve the diaphragmatic activity and lung function in the stroke patients with hemiplegia.