Objective To investigate the effects of early rehabilitation therapy in mechanically ventilated ICU in patients.Methods A randomized controlled trial was carried out.Sixty mechanically ventilated patients,with tracheal intubation or tracheostomy more than 48 h and less than 72 h,were admitted to the intensive care unit (ICU) of the Affiliated Hospital of Medical College Qingdao University from May 2010 to May 2012.These patients were randomly (random number) divided into two groups,the rehabilitation group and the control group,30 patients in each group.In rehabilitation group,rehabilitation therapy was taken twice daily,and the training time and intensity was adjusted according to the condition of the patients.Early rehabilitation therapy included head up actively,transfer from the supine to sit,out of bed,transfer to a chair,standing bedside bed and walking bedside bed.The patient' s body mass index,days to first out of bed,duration of mechanical ventilation,ICU stay,APACHE Ⅱ score,highest FiO2,lowest PaO2/FiO2 and hospital mortality of patients were compared between rehabilitation group and control group.The differences between the groups were compared using t test.Results There was no significant difference in body mass index,APACHE Ⅱ score,highest FiO2,lowest PaO2/FiO2 and hospital mortality between rehabilitation group and control group (P ＞ 0.05).Patients in the rehabilitation group had shorter first out of bed time [(3.8 ± 1.2) d vs.(14.9 ±4.7) d; P =0.00],duration of mechanical ventilation [(5.6±2.1) dvs.(12.7±4.1) d; P=0.005] andICUstay [(7.3±2.8) dvs.(15.2±4.5) d;P =0.01] compared with control group.Conclusions Early rehabilitation therapy was safe and effective in improving the outcomes of mechanical ventilation patient.