Abstract: There is provided a glycosaminoglycan having a backbone structure comprising a repetitive disaccharide bearing a uronic acid residue and a glucosamine residue, and having sulfate groups, wherein substantially no sulfate group bound to the hydroxyl group at the 6-position of the glucosamine residue in the backbone structure is detected as determined by a chemical disaccharide analysis method in which the glycosaminoglycan is decomposed with nitrous acid, reacted with para-nitrophenylhydrazine and analyzed by high performance liquid chromatography, and the molar % of a uronic acid residue having a sulfate group at the 2-position is not less than 45% relative to total uronic acid residues, which is calculated from a disaccharide composition obtained by an enzymatic disaccharide analysis method in which the glycosaminoglycan is digested with glycosaminoglycan-degrading enzymes and analyzed by high performance liquid chromatography. The glycosaminoglycan can be used as an active ingredient of pharmaceuticals.