Provided are a method for producing a fraction containing more than 50% of CH represented by the general formula (1), which comprises at least the step of allowing a glucuronic acid donor, an N-acetylgalactosamine donor, a saccharide receptor, a chondroitin polymerase derived from the Escherichia coli K4 strain, and Mn2+ at a final concentration of 0.02 to 100 mM to coexist, and performing a reaction thereof under conditions of 20 to 40° C. and pH 6 to 8 for 0.5 minutes to 4 hours, and a method for producing a fraction containing more than 50% of CH represented by the general formula (2), which comprises at least the step of performing the reaction under same conditions for 10 hours or longer, which enable industrial scale production of a CH fraction of a controlled even number saccharide and odd number saccharide content ratio by a simple procedure at a low cost. (GlcA-GalNAc)n  (1) GalNAc-(GlcA-GalNAc)n  (2) (In the formula, GlcA represents a glucuronic acid residue, GalNCAc represents a N-acetylgalactosamine residue, - represents a glycosidic bond, and n represents an arbitrary integer.)