Oleanolic acid which is a three pentacyclic triterpenoids isolated from Gentianaceae plants of Swertia mileensis the whole grass or privet fruit, with a free body and glycosides in many plants. Oleanolic acid has a wide range in plants, and the average content is 0.2% - 2%. Cucurbitaceae high content is 1.5% ~ hunchback bottom 2%, privet fruit content of 0.6% ~ 0.7%.