Provided are methods of producing a novel collagen peptide composition, and a DPP-4 inhibitor and antihyperglycemics that comprise the above-mentioned collagen peptide composition. Ginger rhizome-derived enzymes are added to and break down a collagen and/or gelatin solution to generate peptide compositions comprising peptides represented by X-Hyp-Gly (wherein X represents an amino acid residue other than Gly, Hyp, and Pro). The thus obtained collagen peptide composition has a high DPP-4 inhibitory activity and an excellent antihyperglycemic effect.
