Objective To investigate the effects of early resistance training on the success rate of ventilator weaning，off-line efficiency and activity ability in patients with severe respiratory diseases，and to provide guidance for the early rehabilitation of patients with severe respiratory diseases. Methods We selected 64 patients who were admitted to Intensive Care Unit of Respiratory Department of our hospital and received mechanical ventilation from January 2019 to January 2020 as study subjects，and were randomly divided into experimental group and control group with 32 patients in each group. The control group received routine nursing，and the experimental group received early resistance weaning training program led by nurses. The differences of offline success rate，offline efficiency and activity ability after intervention were compared between the two groups. Results After the early resistance off-line training，the success rate of the experimental group was significantly higher than that of the control group （90.63% vs. 65.63%，P=0.015），the duration of ventilator use was significantly lower than that of the control group [（10.80±2.20） d vs.（14.00±3.50） d，P=0.028］，and the incidence of complications was lower（43.75% vs. 68.75%，P=0.014）. The activity ability of experimental group on day 1 and day 3 after offline was significantly better than that of control group（P<0.001）. Conclusion Early resistance off-line training can improve the success rate and off-line efficiency of severe patients，improve the activity level of patients，and promote their disease rehabilitation.