Synthesis of 3″-deoxy and 4″-deoxy Lewisx trisaccharides is described. Phenyl 2,3,6-tri-O-benzoyl-4-deoxy-1-thio-β-d-xylo-hexopyranoside was condensed with a diol of glucosamine to give regio- and stereo-selectively a disaccharide. Stereoselective fucosylation of this disaccharide provided a protected deoxy Lewisx trisaccharide which was deprotected to give the 4″-deoxy Lewisx trisaccharide. Application of the similar synthetic sequence provided the 3″-deoxy Lewisx trisaccharide.