Abstract: Objective：To analyze the clinical features and complications of tracheal intubation in intensive care unit(ICU),and to explore the suitable time and strategy.Methods：One hundred and eighty patients receiving tracheal intubation in ICU were divided into the schedule group and the emergency group.The schedule group(98 cases) had indications for intubation and were fully prepared,while the emergency group(82 cases) underwent intubations without full preparation due to rapid progression of the disease and accidental extubation.The time of intubation,the number of intubation attempts and the related complications of the two groups were recorded.Results：The success rate of intubation was 58.9% on the first attempt in all the 180 cases.The main complication during and after induction was hypoxemia(46.1%).The schedule group were superior to the emergency group,success rate of the second attempt and hypoxemia incidence(P〈0.01).Conclusions：The tracheal intubation in ICU is difficult and tends to have more complications.Early recognition of patients with indications and sufficient preparation are critical to successful bedside intubation.