The purpose of the present invention is to prevent a tire testing device from malfunctioning by preventing rubber waste produced by tire testing from adhering to the tire testing device and a test tire. One embodiment of this invention is a tire testing method including: a contact step for causing a test tire to come into contact with a simulated road surface provided on the outer circumference of a rotating drum, a rotation step for rotating the rotating drum and the test tire that has been brought into contact with the simulated road surface, and a powder dispersion step for dispersing a powder for reducing the adhesiveness of rubber waste produced through abrasion of the test tire on the outer circumferential surface of the rotating drum and/or test tire.