A medium feeding device includes a medium feeding unit that feeds a medium by contacting the medium, a separating unit that presses the medium against the medium feeding unit to separate the medium from subsequent media, and a conveying unit that conveys the medium having been separated by the separating unit. A first guide member is provided between the medium feeding unit and the conveying unit, and configured to guide a surface of the medium on the medium feeding unit side. A second guide member provided is so as to face the first guide member, and configured to guide the medium. The first guide member has a guide protruding portion that protrudes toward the second guide member.