The present invention provides a combination preparation for inducing a specific immune response to an antigenic peptide, which contains (I) the antigenic peptide, and (II) an expression vector encoding a chimeric hepatitis B virus core antigen polypeptide, into which the antigenic peptide has been inserted or added, wherein said antigenic peptide is inserted in a region of amino acid residues 74-87 or 130-138 of the hepatitis B virus core antigen polypeptide, or added to the N-terminal or C-terminal of the hepatitis B virus core antigen polypeptide, wherein the antigenic peptide of (I) and the expression vector of (II) are substantially simultaneously administered to a subject.