Objective:To investigate the risk factors related to intensive care unit (ICU) readmission .Methods :A total of 2491 patients who had been transferred into Department of Critical Care Medicine of Zhongshan Hospital ,Fudan University from Nov 2008 to Dec 2011 were included .Clinical data of all the patients during their first admission to ICU were collected .All the patients were classified into non‐readmission group(Group A) and readmission group(Group B) on the basis of whether there was readmission to ICU .All the patients’ treatments were conducted under supervision of attending intensivist and in accordance with routine treatment of Department of Critical Care Medicine and related clinical guidelines .Logistic regression was performed in multivariate analyses of ICU readmission .Results:If the first admission to ICU was due to emergency ,then the chance of ICU readmission was raised(HR=4 .929 ,95% CI:1 .936‐12 .549 ,P<0 .01) .If patient underwent tracheotomy during the first ICU stay ,then the chance of ICU readmission increased (HR= 3 .395 ,95% CI:1 .622‐7 .107 , P< 0 .01) . Conclusions :Both the admission to ICU under emergency and the tracheotomy during the first ICU admission are independent risk factors for ICU readmission .