A medium discharging device includes a first tray, a second tray receiving a medium from the first tray, a supporter which is configured to be displaced from a retreat position in the first tray and an advance position above the second tray and which supports the medium, an aligner which is provided in the supporter and that aligns a first end portion which is an upstream end portion in a discharge direction of the medium supported by the supporter, to be displaced together with the supporter, and a restrictor configured to be displaced between a restriction position where an upstream movement of the first end portion of the medium in a position of the aligner in the discharge direction and a non-restriction position where the movement is not restricted, when the supporter is in the advance position.