A recording medium placement device includes a placement unit in which a recording medium is placed; a guide member provided along an edge of the recording medium and movable in a first direction orthogonal to the edge, the edge being at a first position; a distance detection unit that detects a distance between the guide member and the edge; a drive unit that moves the guide member in the first direction until the distance detection unit detects that the guide member contacts the recording medium; a gap length calculation unit that calculates a length of a gap between the recording medium and the guide member when a movement of the guide member is stopped using a detection output from the distance detection unit; and an adjustment unit that moves the guide member to the edge at the first position based on the length of the gap.