Multiblock glycopolymers have gathered attention because of their potential use as effective ligands for sugar-binding proteins. The authors report the quantitative preparation of multiblock glycopolymers by reversible addition-fragmentation chain transfer polymerization. The optimized polymerization condition enabled the complete monomer incorporation into the elongating polymer chains at each polymerization step. The structure of the heptablock glycopolymer was well-defined (polydispersity index <1.35), and their molecular recognition against lectins was evaluated.