A hole plug has a head portion, a leg portion protruding from the head portion, and a flange portion protruding on an upper circumference of the leg portion. The leg portion includes an inner wall having an approximately cylindrical shape and connected to the head portion; and an outer wall extending along the inner wall with a gap among the inner wall from a folded portion provided in an end portion of the inner wall, and forming a bendable thin-walled portion. The thin-walled portion is elastically bent by an external force to be capable of transitioning from a first usage aspect in which the outer wall is locked in the hole with the thin-walled portion being in a non-bending state to a second usage aspect in which a force larger than the first usage aspect is provided to pressure contact relative to the hole.