A significant number of terpenoid compounds are glycosides with the sugars linked to the active groups. Sometimes, the glycosidic residue is crucial for their activity, but in other cases glycosylation only improves pharmacokinetic parameters. Enzymatic glycosylation of terpenoids is a useful tool due to the high selectivity and the mildness of the reaction conditions, in comparison with chemical methods. Several types of biocatalysts have been used in the enzymatic glycosylation of terpenoids. These include the use of glycosyltransferases, trans-glycosidases, and whole-cell biotransformation systems capable of regenerating the cofactor, such as fungi, bacteria, plant-cell cultures, etc. Many biosynthesized terpenoid glycosides display medicinal and pharmacological properties and can be used as pro-drug substances. These terpenoid glycosides have also been employed as food additives (e.g. low-caloric sweetener compounds) and cosmetics, and even have applications as controlled-release fragrances.