Researches on biological activity of oligosaccharides and their complexes are of important biogical significance. It is very important to synthesize special α or/and β glycoside in order to synthesize complicated oligosaccharides and their complexes by chemical strategies. Up to nowadays, studies on strategies of chemical stereoselective design and synthesis of oligosaccharides and their complexes have been regarded as one of the most remarkable fields in glycochemistry, and have been paid much attention. This review describes the development of highly stereoselective synthesis of oligosac-charides decades.

Key words: stereo-selectivity, neighboring group participation, intramolecular aglycon delivery, oligosaccharide synthesis