Abstract: Provided is a test method that allows mutagenicity on a mammal including a human to be confirmed accurately and simply in a short time. Specifically, provided is a mutagenicity test method, including the steps of: (1) culturing a transformant of a mammalian cell harboring a recombinant vector including a p53 binding sequence, a minimal promoter that can function in the mammalian cell, and a reporter gene linked so that the gene can be expressed by the minimal promoter, in the presence of a test substance for a predetermined time; and (2) assessing whether or not the test substance affects an expression amount of the reporter gene in the transformant by comparing an expression amount of the reporter gene in the transformant cultured in the step (1) to an expression amount of the reporter gene in the transformant free of contact with the test substance.