Abstract The (-)-enantiomer of Corey lactone Ia has been separated from its (+)-enantiomer Ib via enantioselective esterification of the latter using glycerol tributyrate and catalytic amount of lipase from Candida cylindracea (EC 3.1. 1.3) in an aprotic solvent at 20 to 40 C during 5 to 48 h. The Ic obtained has been separated from Ia by column chromatography and converted back to Ib by acid catalyzed transesterification with methanol.