Aim To explore the effect of Ginseng polysauharides on changes of lipid peroxidation in hepatic ischemia reperfusion injury and its mechanism. Methods 30 rabbits were randomly divided into control group,ischemia-reperfusion (IR) group and Ginseng polysauharides group. Alanine aminotransferase (ALT),superoxide dismutase (SOD),glutathione peroxidase(GSH-Px),xanthine oxidase(XO),malondialchehyche (MDA) were recorded,and the liver organizational structure change were observed under the light microscope. Results In IR group,the plasma SOD,GSH-Px activity declined gradually 45 minutes after ischemia and this phenomenon continued for 45 minutes after reperfusion. The activity of ALT,XO and the content of MDA clearly increased. In Ginseng polysauharides group,the plasma SOD,GSH-Px activity had no prominent decline; the activity of ALT,XO and content of MDA had no obvious increase,especially when 45 minutes after reperfusion,the SOD activity was much higher,and the ALT and XO activity,content of MDA were much lower than that in IR group of the same period (P<0.01). The SOD and GSH-Px activity of IR group in liver increased compared with control group,but decreased in Ginsen polysauharide group compared with IR group (P<0.01). The XO activity and the MDA content of the IR group in liver decreased compared with control group,but increased in Ginsen polysauharide group compared with IR group (P<0.05 or 0.01). In IR group,the morphology structure of hepatic cell obviously abnormal,but in Ginseng polysauharides group,relatively mild injury occurred to the hepar. Conclusion Ginseng polysauharides can reduce the activity of XO and suppress the production of oxygen-derived free radicals; tone up antioxidase like SOD,GSH-Px and suppress lipid peroxidization,thus effectively reduce the injury caused by hepatic ischemia reperfusion.