The present invention provides a WT1-derived HLA-DRB1*0405 bindingantigen peptide, a polynucleotide encoding said peptide, a helper Tcell inducer comprising said peptide or polynucleotide, and the like. It isrelated to a partial peptide consisting of 10 - 25 contiguous amino acids inthe amino acid sequence of human WT1 shown in SEQ ID NO: 1, whichbinds to HLA-DRB 1*0405 and induces helper T cells, a polynucleotideencoding said peptide, or a helper T cell inducer comprising said peptide orpolynucleotide.