Background: Treatment of critical illness on intensive-care-units (ICU) results often in persistent invasive endotracheal intubation which might delay rehabilitation and increases the risk of mortality. Recent longitudinal studies have described the recovery of critically ill people, but the detailed time course of decannulation in patients with chronic critical illness with ICU-acquired muscle weakness (ICUAW) is not well known. Aim: The aim of our study was to describe the decannulation times and associated risk factors in patients who are chronic critically ill with ICU acquired weakness. Design: This is a cohort study. Setting: Postacute and rehabilitation units. Population: Chronic critically ill patients with ICUAW and tracheostomy tube. Methods: We calculated the time until decannulation and used possible predictor variables to explain this time course. RESULTS: We included 122 patients with ICUAW. Successful decannulation of the tracheostomy tube was achieved after a median of 40.5 days (interquartile range= 44) after study onset and after a median of 89 days (interquartile range= 58) after onset of primary illness. Our final multivariate Cox-Proportional Hazard model included two main risk factors for decannulation: the amount of medical tubes such as catheters at admission to the rehabilitation center (adjusted hazard ratio [HR]=1.572 (95% CI: 1.021 to 2.415) and the duration of weaning from respirator in days (adjusted HR= 1.02 per day (95% CI: 1.006 to 1.03). No adverse events occurred. Conclusions: We described the detailed time course of decannulation in the rehabilitation of chronic critically ill patients and no adverse events were observed. Taken many single factors into account the quantity of medical tubes and the duration of weaning from respirator were associated risk factors for decannulation in this population. Clinical Rehabilitation Impact: Knowing an exact time course of decannulation supports medical decisions in clinical rehabilitation and might help to give a prognosis for decannulation. The amount of medical tubes and the duration of weaning from respirator may highly influence decannulation.