ObjectiveTo investigate the risk factors for early postoperative cognitive dysfunction (POCD) in elderly patients after colorectal cancer surgery.Methods One hunderd and twenty ASA Ⅱ or Ⅲ patients aged ≥ 65 yr undergoing colorectal cancer surgery were divided into POCD group and non-POCD group according to the results of the Mini-Mental State examination (MMSE) at 7th day after operation.Age,weight,sex,the educational level,anatomical location of the tumor,TNM stages,complications,preoperative TCM syndrome type,duration of anesthesia,emergence time,the blood loss during opertion and the number of intraoperative hypotension were recorded.The cognitive function was assessed at 1 d before operation and at 1,3,7 d after operation using MMSE.The risk factors for POCD were analyzed by multivariate logistic regression analysis.ResultsThe incidence of POCD was 29.2 ％.Logistic regression analysis results indicated that age,the educational level,anatomical location of the tumor and the number of intraoperative hypotension were the risk factors for POCD( P ＜ 0.05).Conclusion Age,the educational level,anatomical location of the tumor and the number of intraoperative hypotension are risk factors for POCD in elderly patients after colorectal cancer surgery.