A medium feeding device includes a storage unit that stores media in a form of a sheet, a delivery unit that is disposed downstream in a medium delivery direction relative to the media stored in the storage unit and that delivers the media individually, a transfer unit that is disposed above the storage unit and that adheres by suction to each of the media stored in the storage unit and transfers the media to the delivery unit, and a fluffing unit that is disposed beside the media stored in the storage unit in a direction intersecting the medium delivery direction. The fluffing unit fluffs an upper-side region of the media in a state of being separated, by blowing air toward a side of the media during a feeding job of the media and during a post-feeding period that is a predetermined period after completion of the feeding job. The medium feeding device further includes a suppression unit that suppresses movement of the media toward the delivery unit side during air blowing performed by the fluffing unit in the post-feeding period.