The invention relates to a preparation method for 24-hydroxyl-glycyrrhetinic acid, and relates to the field of pharmaceuticals and chemicals. According to the invention, the 24-hydroxyl-glycyrrhetinic acid is extracted from glycyrrhizinate; the advantages of simple extraction process, strong operability, high effective substance yield, full utilization of resources and the like are realized; compared with glycyrrhetinic acid, the prepared 24 hydroxyl-glycyrrhetinic acid has more superior pharmacological activity, absorption efficiency and the like; the method is suitable for large-scale promotion and application.