beta-Glycosidases catalyze the synthesis of glycosides when a nucleophilic acceptor other than water is present in the reaction medium. We describe the enzymatyc synthesis of 2-beta-D-galactopyranosyloxyethyl methacrylate (GalEMA) starting from 2-hydroxyethyl methacrylate (HEMA) and p-nitrophenyl-beta-D-galactopyranoside (pNPG) using a beta-glycosidase activity present in the thermophilic archaeon Sulfolobus solfataricus. This thermophilic enzyme catalyzes the transfer of the galactopyranosyl unit from pNPG to the HEMA hydroxyl group by the formation of a new beta-glycosidic bond. The conditions of the biocatalytic system have been optimized to obtain high yield of GalEMA.