This paper studies the extraction and identification of ginsenoside Re from ginseng fruits and investigates the effect and mechanism of ginsenoside Re of protecting acute renal ischemia-reperfusion injury in rats.Having been smashed,the ginseng fruits were ultrasonically extracted twice with 95% ethanol for 30min each.Having been concentrated,the solution was dissolved with distilled water and separated by two-column chromatography,of which one was packed with macroporous resin D4020,and the other was packed with macroporous resin D941.The raw product was dissolved with methanol and was purified by elution on a Si gel column,finally ginsenoside Re was obtained.The structure of the ginsenoside Re was analyzed by the thin-layer chromatography and NMR methods,and HPLC was carried for the content determination.The model of acute renal ischemia-reperfusion injury in rats was established after ischemia for 1 h and reperfusion for 1 h or 24 h,serum SOD(superoxide dismutase),MDA(malondialdehyde) and plasma TXB2(thromboxane B2) and 6-keto-PGF1α were detected.The results show that it has accurately,fast,convenient merits and so on.Ginsenoside Re has a protective effect on acute renal ischemia-reperfusion injury in rats,the mechanism may be related to improving the imbalance of thromboxane A2(TXA2)/prostacyclin(PGI2) and inhibiting lipid peroxidation reaction.