An image reading device includes an image reading unit, a conductive member, a switching portion, and a switching control portion. The image reading unit includes a light emitting portion and a light receiving portion. The light emitting portion irradiates light on a document sheet that is conveyed while in contact with an upper surface of a plate-like contact member. The light receiving portion outputs image data corresponding to light reflected from the document sheet. The conductive member is provided on a lower surface of the contact member. The switching portion is switched between an on-state and an off-state so as to select between a state where the conductive member is grounded or a state where the conductive member is not grounded. The switching control portion controls switching of the switching portion.