A post-processing device includes a processing stacking portion that allows media to be stacked thereon; a binding member that performs a binding process on the media; a medium ejection portion on which the media ejected from the processing stacking portion are stacked and which moves upward and downward; and a pressing member that presses an upper surface of the media on the medium ejection portion. When media that have not been subjected to the binding process are stacked on the medium ejection portion, the pressing member and the media are brought into contact with each other. When media that have been subjected to the binding process are stacked on the medium ejection portion, the pressing member and the media are disposed further away from each other than when media that have not been subjected to the binding process are stacked on the medium ejection portion.