Abstract: Objective: To study the influence of Vitamin E on the hyperphosphorilation tau protein in the brains of Alzheimer disease(AD) rats by means of oxidative stress.Methods: Thirty-six AD rats were randomly divided into three groups:sham operation group,model group and model treatment group(each consisting of 12 rats).The models were established by injecting amyloid-β protein into the left amygdale of the rats.The sham operation group received injection of solvent only,and the model treatment group were additionally fed Vit E 10 mg once a day by gastrogavage.The ability of learning and memory of the rats were detected by Y-maze and the expression of P_ser-262-tau in hippocampus tissues was estimated by immunohistochemistry methods.Results: The ability of learning and memory of the rats in the treatment group was lower than that in sham operation group(P<0.01),but higher than that in model group(P<0.01).Vietmin E could depress the expression of P_ser-262-tau in the hippocampus tissues of AD rats.Conclusions: Vitamin E depresses the expression of P_ser-262-tau in the hippocampus tissues of AD rats and improves the learning and memory ability of the rats,suggesting that vietmin E can protect the tau protein from hyperphosphorylation in rats.