An image reading device includes an upstream-side conveying unit (92) configured to convey an original; a reading unit (95) configured to read an image of the original conveyed by the upstream-side conveying unit (92); and a guide unit arranged between the upstream-side conveying unit (92) and the reading unit (95) to guide the original. As seen from a direction parallel to a reading surface (95a) of the reading unit (95) and perpendicular to an original conveying direction in a reading position (B) of the reading unit (95), an original conveying position (X 1 ) for applying a conveying force to the original using the upstream-side conveying unit (92) is arranged in a lower side from the reading position (B) in a direction perpendicular to the reading surface (95a) of the reading unit (95), and the guide unit (120, 121) is configured such that the original passing through the original conveying position (X 1 ) is guided to an upper direction.