A chemically modified water-soluble elastin that is obtained by subjecting to N-acylating some or all of the primary amines and secondary amines contained in the molecule of a high molecular weight water-soluble elastin and coupling some or all of the carboxyl groups contained in the molecule with the amino group of an amino acid alkyl ester.A chemically modified water-soluble elastin/collagen mixed gel obtained by mixing a collagen with a chemically modified water-soluble elastin that is obtained by subjecting to N-acylating some or all of the primary amines and secondary amines contained in the molecule of a high molecular weight water-soluble elastin and coupling some or all of the carboxyl groups contained in the molecule with the amino group of an amino acid alkyl ester.
