The present invention provides an immunity-inducing agent comprising a polynucleotide-peptide conjugate or a pharmaceutically acceptable salt thereof as an active component, wherein the polynucleotide-peptide conjugate consists of: a single-chain polynucleotide or polynucleotide derivative comprising a CpG motif; a peptide; and a spacer which is covalently bonded at one end thereof to the polynucleotide or polynucleotide derivative and covalently bonded at the other end thereof to the peptide, wherein the peptide is a peptide modified by substituting one or more contiguous amino acids at the N-terminus of an MHC-binding peptide with an amino acid having a reactive functional group which allows for the formation of a covalent bond with the spacer, wherein the one or more contiguous amino acids contain no anchor residues for MHC binding.