This invention relates to a peptide-polymer conjugate of the following formula: A-G1-L-G2-B, wherein A is a polymer moiety; each of G1 and G2, independently, is a bond or a linking functional group; L is an alkenylene or alkynylene moiety; and B is a peptide moiety. Also disclosed are a method for preparing a peptide-polymer conjugate and its use in treating hepatitis C virus infection or hepatitis B virus infection.