The present invention relates to a composition for preventing, treating or ameliorating ischemic reperfusion injury, comprising a bile acid. According to the present invention, bile acids increase the nuclear level of beta-catenin, prevent the release of mitochondria permeable transition pore (mPTP), improve tissue damage in animal models of ischemic reperfusion injury, and improve infarction of infarction. Due to its excellent size-reducing effect, it can be usefully used to prevent, treat or ameliorate ischemic reperfusion injury.本発明は、胆汁酸を含む虚血性再灌流損傷の予防、治療または改善用組成物に関する。本発明によると、胆汁酸は、ベータ-カテニンの核内水準を増加させ、mPTP(mitochondria permeable transition pore)の開放を妨害し、虚血性再灌流損傷動物モデルで組織の損傷を改善し、梗塞の大きさを減少させる優れた効果があるため、虚血性再灌流損傷の予防、治療または改善に有用に使用することができる。