A medium feeding device comprising: a placement unit on which a medium (P) can be placed; a pair of edge guides that is provided at the placement unit such that the edge guides are movable in a medium width direction (X) to guide edges of the medium in the medium width direction that is a direction intersecting a medium feeding direction (Y); feeding rollers configured to feed the medium placed on the placement unit; a medium feeding path (T) through which the medium fed from the placement unit can pass; a path state detection section configured to detect a detection value in accordance with a state of the medium feeding path; a guide position detection section configured to detect positions of the edge guides; and a control section configured to determine whether or not the detection value detected by the path state detection section has exceeded a threshold value, wherein the control section is configured to change the threshold value in accordance with a detection signal of the guide position detection section; wherein the control section is configured to determine the positions of the pair of edge guides with respect to the feeding rollers and the central position in the medium width direction on the basis of the detection signal of the guide position detection section, and wherein the control section is configured to set the threshold value that is applied in a case in which the feeding rollers are not located at the center of the pair of edge guides in the medium width direction to be smaller than the threshold value applied in a case in which the feeding rollers are located at the center of the pair of edge guides on the basis of the detection signal of the guide position detection section. a placement unit on which a medium (P) can be placed; a pair of edge guides that is provided at the placement unit such that the edge guides are movable in a medium width direction (X) to guide edges of the medium in the medium width direction that is a direction intersecting a medium feeding direction (Y); feeding rollers configured to feed the medium placed on the placement unit; a medium feeding path (T) through which the medium fed from the placement unit can pass; a path state detection section configured to detect a detection value in accordance with a state of the medium feeding path; a guide position detection section configured to detect positions of the edge guides; and a control section configured to determine whether or not the detection value detected by the path state detection section has exceeded a threshold value, wherein the control section is configured to change the threshold value in accordance with a detection signal of the guide position detection section; wherein the control section is configured to determine the positions of the pair of edge guides with respect to the feeding rollers and the central position in the medium width direction on the basis of the detection signal of the guide position detection section, and wherein the control section is configured to set the threshold value that is applied in a case in which the feeding rollers are not located at the center of the pair of edge guides in the medium width direction to be smaller than the threshold value applied in a case in which the feeding rollers are located at the center of the pair of edge guides on the basis of the detection signal of the guide position detection section. <EOS>