An image reading apparatus includes an opening/closing unit, an output gear, an apparatus main body having an image reading unit, a retard roller, and an input gear, and includes an opening/closing unit having a pickup roller, a feed roller, a feed roller shaft, a drive shaft, and an adjustment support portion. The feed roller shaft supports the feed roller. The drive shaft is connected at one end side thereof to the feed roller shaft via a coupling. The feed roller shaft is removable from the drive shaft. The input gear meshes with the output gear to transmit a driving force to the feed roller where the opening/closing unit is closed, and is separated from the output gear where the opening/closing unit is opened. The adjustment support portion supports the other end side of the drive shaft to adjust a position for supporting the drive shaft.