Abstract: Objective To investigate the relationship between alcohol-induced oxidative stress and cognitive impairment. Methods Fifty alcohol dependent male patients met DSM-IV Criteria and 40 healthy subjects were enrolled into this study.The repeatable battery for the assessment of neuropsychological status(RBANS) were used to assess the cognitive function,and the levels of the main mark of plasma free radical metabolism such as the activity of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px) and malondialdehyde(MDA) were tested. Results There was no significant difference in the age and educational level between the two groups.In the observation group,the levels of SOD and GSH-Px decreased,while the level of MDA increased,and the score for total RBANS and every item decreased(P<0.05).The total RBANS score did not show obvious association to the level of SOD.However,the total RBANS score(2.22±0.03,P<0.05),immediate memory factor(2.23±0.03,P<0.05) and attention factor(2.07±0.04,P<0.05) showed relations to the levels of GSH-Px,and total RBANS score(2.13±0.04,P<0.05),immediate memory factor(2.18±0.04,P<0.05),breadth of vision actor(2.12±0.04,P<0.05),attention factor(2.46±0.02,P<0.05) and delayed memory factor(2.43±0.02,P<0.01) showed correlation to the level of MDA. Conclusion The alcohol dependent patients are with oxidative stress and cognitive impairment.The abnormal cognitive function mat be related to the oxidative stress.