A medium suction support device includes a medium support table, a suction unit, a plurality of flexible tube members and a sliding member. Through-holes are formed in the medium support table to pass through the medium support table. The suction unit is disposed on a side of the back surface to suction the recording medium disposed on the medium support surface via the through-holes. One opening end of each of the flexible tube members surrounds a corresponding one of the through-holes on the back surface. The sliding member is configured to move in parallel along the back surface. The sliding member has openings formed in an opposing surface facing the back surface with each of the openings being configured to respectively accommodate the other opening end of a corresponding one of the flexible tube members. The openings have different lengths in a parallel movement direction of the sliding member.