PURPOSE: To easily obtain the subject compound useful as a medicine, without using complicate processes such as methyl-esterification and saponification, in high yield, by using 3-oxo-18β-glycyrrhetinic acid as a raw material and reducing the material with a metal trialkyl borohydride.

CONSTITUTION: The objective compound of formula I can be produced by using 3-oxo-18β-glycyrrhetinic acid as a raw material and reducing the material with a metal trialkyl borohydride such as potassium tri-sec-butyl borohydride and lithium tri-sec-butyl borohydride in the presence of an organic solvent such as tetrahydrofuran. The 3-epi-18α-glycyrrhetinic acid (3α-hydroxy-18α- glycyrrhetinic acid) is produced by using 3-oxo-18α-glycyrrhetinic acid as a raw material and reducing the material with a metal trialkyl borohydride in an organic solvent.