Dihydrooleanolic acid (VI) was prepared from oleanolic acid (I) as follows. Acylation of (I) with Ac2O in pyridine gave 3-acetoxy oleanolic acid (II), which was converted to the corresponding methyl ester (III) upon treatment with diazomethane. Subsequent epoxidation of (III) by means of m-chloroperbenzoic acid afforded the 12,13-epoxy derivative (IV). Rearrangement of epoxide (IV) by refluxing with boron trifluoride etherate in benzene led to ketone (V). Wolff-Kishner reduction of the keto group of (V) with hydrazine and KOH in tripolyethylene glycol furnished dihydrooleanolic acid (VI). The title compound was then obtained by esterification of (VI) with 2,2-dimethylsuccinic anhydride (VII).