The purpose of the invention is to provide a glucan containing at least one residue selected from an N-acetylglucosamine residue and a galactose residue, and a modified product thereof. A branched glucan according to the invention is a branched glucan in which at least one residue selected from an N-acetylglucosamine residue and a galactose residue is linked via an a-1,4-linkage to each of two or more non-reducing ends among a plurality of non-reducing ends of a branched a-1,4-glucan, and at positions other than the non- reducing ends of the branched a-1,4-glucan, either of an N-acetylglucosamine residue or a galactose residue is not present.
