Abstract: Objective: To analyse the risk factors for postoperative confusion in a surgical intensive care unit. Methods: 388 consecutive patients in our surgical intensive care unit were retrospectively studied and classified into two groups. Patients with postoperative delirium were group A, the others were group B. Results: Postoperative confusion occurred in 3.1% of 388 patients. The incidence of the aging population older than 65 were 6.6 %（9/136）and that of the other younger population were 0.4 %（1/252）. The incidence of patients used methylprednisolone no less than 1000mg a bolus were significantly higher than the other patients（P＜0.05）. Conclusions: Older age and large dosage corticosteroid were the risk factors for postoperative confusion.