The present invention provides a compound expressed by formula (1) or a salt, etc., thereof. In formula (1): Xa and Ya represent single bonds, etc.； a cancer antigen peptide (A) represents an MHC class I-restrictive WT1 peptide comprising a 7-30 residue amino acid； R1 represents a hydrogen atom, a group expressed by formula (2) (in the formula, Xb and Yb represent single bonds, etc., and a cancer antigen peptide (B) represents an MHC class I-restrictive WT1 peptide comprising a 7-30 residue amino acid and having a different sequence to that of the cancer antigen peptide (A)), or a cancer antigen peptide (C)； and a cancer antigen peptide (C) represents an MHC class I-restrictive WT1 peptide or an MHC class II-restrictive WT1 peptide that comprise a 7-30 residue amino acid which contains one cysteine residue, and have a different sequence to that of the cancer antigen peptide (A).本發明提供式(1)所表示之化合物或其鹽等：[式中，Xa及Ya表示單鍵等，癌抗原胜肽A表示包含7~30殘基之胺基酸的MHC I類限制性WT1胜肽，R1表示氫原子、式(2)所表示之基、或癌抗原胜肽C：(式中，Xb及Yb表示單鍵等，癌抗原胜肽B表示序列與癌抗原胜肽A不同且包含7~30殘基之胺基酸的MHC I類限制性WT1胜肽)，癌抗原胜肽C表示序列與癌抗原胜肽A不同且包含包括1個半胱胺酸殘基之7~30殘基之胺基酸的MHC I類限制性WT1胜肽或MHC II類限制性WT1胜肽]。
