Provided is a novel T cell epitope peptide of Japanese cypress pollen allergen different from known Japanese cypress pollen allergens. A peptide selected from the group consisting of amino acid sequences shown by SEQ ID NO. 3-16, or a peptide having 1-3 amino acids substituted and/or 1-10 amino acids deleted or added in this peptide, the peptide having T cell stimulatory activity.本發明提供一種與已知之檜木花粉過敏原不同之新穎檜木花粉過敏原之T細胞抗原決定位肽。一種肽,其係選自由序列編號3~16所示之胺基酸序列所組成之群中者、或者該肽中置換1~3個胺基酸及/或缺失或附加1~10個胺基酸者,且具有T細胞刺激活性。