A medium-discharging device includes: a medium-discharging section that discharges a medium; a medium-receiving tray that receives the medium discharged by the medium-discharging section; a light-emitting section that emits light to the medium-receiving tray; and a control section that controls the light-emitting section, in which the medium-receiving tray is configured to switch between a first state in which the medium-receiving tray is stored in an apparatus main body that includes the medium-discharging section and a second state in which the medium-receiving tray protrudes from the apparatus main body, and the control section controls the light-emitting section in accordance with a state or operation of the medium-receiving tray.