Objective To investigate the efficacy of erythropoietin (EPO) on cerebral ischemia of patients after intracranial aneurysm surgery.Methods Sixty patients with cerebral ischemia after operation of intracranial aneurysm,admitted to our hospital from May 2006 to August 2010,were randomly divided into control and treatment groups (n=30).Control group received conventional treatment,while the other group,on the basis of conventional therapy,was hypodermically given EPO at a dosage of 3000 IU for a consecutive 3 days.U.S.National Institutes of Health Stroke Scale (NIHSS) was used to score the patients on the admission day,1,2,3,4 and 5 weeks after EPO treatment; and diffusion-weighted imaging (DWI) of MRI was used in determining the changes of cerebral ischemic area on the ischemic day and l,2,3,4 and 5 weeks after ischemic.Results NIHSS scores of the EPO group (9.4±1.9,11.3±2.3,8.7±1.7) at 3,4 and 5 weeks after treatment were significantly higher as compared with those in the control group (10.8±2.2,7.9±1.6,10.1±2.3) (P＜0.05).Similarly,3,4 and 5 weeks after treatment,the reducing percentage of cerebral ischemia area in the EPO group (21.6±4.1,27.5±5.3,32.8±5.5)％ was larger than that in the control group (16.8±3.1,18.9±3.3,19.5±3.4)％ (P＜0.05).Conclusion EPO may play an effective role in cerebral ischemia of patients after intracranial aneurysm operation.