An image scanning device including: a conveyance path which conveys originals; a first scanning means and a second scanning means which are placed such that they sandwich the conveyance path; and a white reference member used for adjusting the white levels of the scanning means; wherein at least one of the first scanning means, the second scanning means and the white reference member is movable; the first scanning means and the second scanning means can scan the same surface of said white reference member since the first scanning means or the second scanning means is moved or the white reference member is moved.