In a scanner, a medium transport apparatus includes an apparatus main body including a medium transport path from a supply unit, which supplies a medium, to a discharge unit, which discharges the medium, a switcher that switches an attitude of the apparatus main body with respect to a mounting surface on which the apparatus main body is mounted, and a controller that, when the attitude of the apparatus main body with respect to the mounting surface is switched, performs control in accordance with the attitude after the switching.