Our purpose is to develop an efficient synthetic method of obtaining oligosaccharide unit in sufficient amounts to study functions of glycans. Many exoglycosidases have been used as tools for the oligosaccharide synthesis. In contrast, a limited number of reports are available on the utilization of endoglycosidases. We describe herewith the efficient synthetic method of useful oligosaccharides and derivatives as biomaterials utilizing lysozyme, cellulase, and lacto-N-biosidase-mediated transglycosyltions.