Objective To establish the rehabilitation program of external diaphragm pacer and to explore its preventive effect on ventilator-induced diaphragmatic dysfunction（VIDD） in patients with ICU non-invasive mechanical ventilation. Methods Through the literature review,group meeting and pre-experiment,a program was formulated to prevent VIDD in patients with non-invasive ventilation in ICU. Patients with non-invasive ventilation were conveniently selected from September 2020 to June 2021 in a respiratory intensive care unit of a tertiary hospital in Henan province. They were divided into 2 groups by random number table method. On the basis of routine nursing care,the experimental group was given the external diaphragm pacer training program,and the control group was given routine nursing program. The incidence of VIDD,diaphragm thickness score,diaphragm displacement and blood gas analysis were compared between 2 groups after the intervention. Results A total of 74 patients were included with 10 cases fallen off,and finally 64 cases were included with 32 cases in the experimental group and 32 cases in the control group. After the intervention,the incidence of VIDD was 6.25% in the experimental group,while that was 43.75% in the control group. The difference between 2 groups was statistically significant（P=0.001）. Conclusion The external diaphragm pacer rehabilitation program can reduce the incidence of VIDD and improve diaphragm and respiratory function in patients with ICU non-invasive mechanical ventilation.