[Objective] The aim was to study the antioxidant effect of polyphenols from pomegranate peel in vivo. [Method] The Kunming rats were randomly divided into a control group, a low-dose group, a middle-dose group and a high-dose group,n=10; the protein content, the activities of the superoxide dismutase(SOD) and the glutathione peroxidase(GSH-PX), the content of the maleic dialdehyde(MDA) in serum and liver tissue of the rats from different groups were determined. [Result]The polyphenols of pomegranate peel could increase protein content, activities of superoxide dismutase(SOD) and glutathione peroxidase(GSH-PX) in serum and liver tissue, and decrease the maleic dialdehyde(MDA) content simultaneously. [Conclusion] Polyphenols of pomegranate peel have strong antioxidant activity in vivo.