Provided is a promoter showing transcriptional activity in a mesothelioma-specific manner and showing low transcriptional activity in other kinds of cancer cells and normal cells including mesothelium. Also provided are applications of the promoter, and more specifically, a gene therapy vector and a therapeutic agent for mesothelioma each including the promoter. The promoter includes a CRI1 gene-derived promoter, which is one kind of mesothelioma markers. The use of a vector including a cell death-inducing gene or a cell lysis-inducing gene as a transgene and carrying the CRI1 gene-derived promoter upstream of the transgene can induce a cell death or cell lysis action in a mesothelioma-specific manner. That is, the gene therapy vector and the therapeutic agent for mesothelioma each include a virus vector carrying the CRI1 gene-derived promoter.