An image reading device includes a tubular-shaped housing, a cylindrical document setting section that is arranged in the housing and on which a document wound in a cylindrical shape is set, an document leading edge inlet into which a leading edge of the document in a rotation direction enters when the document set in the document setting section receives rotational forces RL and RR and rotates, a transport path that is arranged in the housing and along which the document that has entered the document leading edge inlet is transported in a transport direction F by receiving a transport force Cf, a reading section configured to read the image of the document transported along the transport path, and a discharge section to which the document read by the reading section is discharged.

An image reading device includes a reading unit that includes a transparent member, a sensor for reading an image on a sheet conveyed by a conveyance roller via the transparent member, a case accommodating the sensor, and a first contact portion and a second contact portion located at the case. The reading unit is movable to each of a first position where the image on the sheet is read by the sensor and a second position where the transparent member is exposed to an outside and the first and second contact portions contact the conveyance unit. When the transparent member is pressed in a state where the reading unit is located at the second position, a backup portion contacts the other of the case and the conveyance unit so that the conveyance unit supports the case.

A medium feeding device includes a placement section on which a medium group is supported; a raising and lowering section configured to raise and lower the placement section; a pickup unit that includes a pickup roller that comes into contact with an upper section of the medium group and a support section that applies a downward force to the pickup roller, and that feeds a medium in order from a top in a feed direction while applying a downward pressing force to the medium group from the pickup roller; a control section; and a detection section configured to detect the pressing force, wherein the control section causes the raising and lowering section to raise and lower the placement section such that a detected pressing force falls within a target range.