A magnet conveyance positioning device including a conveyance unit and an attachment device attached to the conveyance unit to move integrally with the conveyance unit. The attachment device includes a support unit abutting on a object and supporting the conveyance unit from the object, a holding unit provided movably relative to the support unit to detachably hold the magnet, and a driving unit moving the holding unit so that the magnet approaches the object in a state where the support unit is abutted on the object.