Provided are a motor having a small number of parts and provided with waterproof performance in a low-cost method, and a positioning device and a conveyance device that are positioned and driven by the motor. The motor includes a columnar motor body that is formed with a center hole penetrating in an axial direction, and a housing for accommodating the motor body. The housing includes a cylindrical part that covers an outer peripheral surface of the motor body; a rotation output part provided on an upper side of the cylindrical part in the axial direction and fixed to rotary bodies of the motor body; and a fixed part provided on a lower side of the cylindrical part in the axial direction and fixed to fixed bodies of the motor body. The housing is sealed by a sealing mechanism at only one place of the cylindrical part in the axial direction.