The present invention relates to a method and a pharmaceutical composition for treating an atherosclerotic lesion, comprising administering a subject in need thereof an therapeutically effective amount of a composition comprising hypoxia-cultured MSCs obtained by culturing auto- or allo-MSCs under low oxygen conditions.本發明係有關於一種用於治療動脈粥狀硬化之方法及醫藥組成物,其包含對所需者投予一治療有效量的含有缺氧培養之間葉幹細胞之組成物,該間葉幹細胞係於低氧條件下培養自體或異源間葉幹細胞所獲得。