A compound represented by the formula (1): wherein Xa and Ya are each a single bond and the like, cancer antigen peptide A is an MHC class I-restricted WT1 peptide consisting of 7-30 amino acid residues, R1 is a hydrogen atom, a group represented by the formula (2): wherein Xb and Yb are each a single bond and the like, cancer antigen peptide B has a sequence different from that of the cancer antigen peptide A, and is an MHC class I-restricted WT1 peptide consisting of 7-30 amino acid residues, or cancer antigen peptide C, and cancer antigen peptide C has a sequence different from that of the cancer antigen peptide A, and is an MHC class I-restricted WT1 peptide or an MHC class II-restricted WT1 peptide, consisting of 7-30 amino acid residues containing one cysteine residue, or a salt thereof, and the like.