Objective：To investigate the morbidity rate and risk factors of delirium after spinal operation in elderly patients. Methods： From January 2011 to December 2012，200 elderly patients after spinal operation were randomly selected. The following factors：pa－tients’ gender，age，anesthesia method，surgical site（cervical vertebra，thoracic vertebra，lumbar vertebra），duration of surgery，postop－erative recovery time，preoperative psychological state，postoperative sleep，whether in complication of underlying diseases（hyperten－sion，coronary heart disease，diabetes，hyperlipidemia，chronic bronchitis），the amount of bleeding，intraoperative blood pressure，were carried on the risk assessment by means of statistical analysis to predict the responsibility rate for elderly spinal operation patients with postoperative delirium. Results：The morbidity rate of delirium after spinal operation in elderly patients was 11%（22/200）. Logis－tic regression analysis indicated that the morbidity rate of delirium after spinal operation was not clearly correlated with factors of pa－tients’ gender，the amount of bleeding and whether in complication with underlying diseases（P ＞0.05）. It was closely related with age，anesthesia method，surgical site，duration of surgery，postoperative recovery time，intraoperative blood pressure，preoperative psycholog－ical state and postoperative sleep（P＜0.05）；the value of OR and its 95%CI were 7.107（0.238 1 to 1.211 6），12.613（0.869 5 to 6.086 2），6.978（-5.865 9 to-1.131 7），3.697（0.1948 to 6.0705），5.367（1.014 1 to 7.701），3.012（0.067 7 to 5.517 9），6.078（1.130 4 to 6.555 2），3.018（-6.798 9 to -0.668 05）. Conclusion：The morbidity rate of delirium after spinal operation in elderly patients is considerablely high and the major risk factors are advanced in years，general anesthesia，duration of surgery or postoperative recovery time，hypoten－sion，unstable mental state in the preoperative and postoperative sleep disorders.