Abstract： Objective To observe cognitive effects after epidural vs vein postoperative analgesia in older adults. Methods 64 patients, age ≥ 60 years old, ASA grade Ⅰ～Ⅱ, scheduled for abdominal surgery by epidural anaesthesia were divided randomly into two groups:patient controlled epidural analgesia (PCEA)group ( group PCEA, n = 32 ): commenced with a loading dose of 6 ml ( 0.25% ropivacaine with morphine 1.0 ～ 1.5 mg and droperidol 1.25 mg) ,and continuous epidurally infusion of 0.25% ropivacaine( 100 ml with morphine 5 mg and droperidol 2.5 mg) ,the PCEA pump was set up with 1 ml bolus with a 15 min lockout interval and a background infusion at 2.0 ml/h. patient controlled intravenous analgesia ( PC IA) group ( group PCIA, n = 32 ): receiving continuous intravenous analgesia with 0.1% morphine( with droperidol 0.2 mg/ml), commenced with a loading dose of 5.0 ml,the PCIA pump was set up with 1 ml bolus with a 15 min lockout interval and a background infusion at. 1.0 ml/h for postoperative analgesia. Postoperative analgesic effect was assessed by visual analog scales(VAS,0 ～ 100). Results the outcome of cognitive function at the before operation, 1 d and 3 d after operation. Results Both groups were equally effective in postoperative analgesia. about 50% patients had impact of the cognitive function in the group PCIA at 1 d after operation, Compared with the group PCEA, the impact of the cognitive function of group PCIA were more significantly. Conclusion PCEA is more suitable for the postoperative analgesia in the elderly.