An image reading device includes a light source, an image sensor, a transport unit, and a control unit. While, during reading of a target to be read by the image sensor, the control unit causes the transport unit to accelerate the read rate of the image sensor to a reference read rate or to decelerate the read rate thereof from the reference read rate, the control unit causes the light source to light up, within the read time, with timing brought close to a read section from a lighting start point to a lighting end point in the case of reading one line in the reference read time.