A post-processing device includes a stacking portion on which media are stacked; a staple binding device that binds the media together by using a staple and that is movable between staple binding positions at which the staple binding device binds the media together and a supply position that is in a front section in a width direction of the media and at which staples are suppliable to the staple binding device; and a stapleless binding device that binds the media together without using a staple and that is movable between a stapleless binding position at which the stapleless binding device binds the media together and a retracted position that is in the front section. When the stapleless binding device is moved to the retracted position, the staple binding device and the stapleless binding device do not interfere with each other irrespective of a position of the staple binding device.