An image recorder and a method of recording an image on a printing plate are provided. A punch unit for forming punched holes and the like for use in a printing apparatus in the printing plate positions the printing plate by bringing a pair of reference pins into contact with an edge of the printing plate, and punches the printing plate. Next, the printing plate is transferred to a recording drum in the image recorder for image recording. The recording drum is provided with positioning pins mounted upright in substantially the same location as the reference pins of the punch unit. Thus, a portion of the edge of the printing plate which made contact with the reference pins of the punch unit is also brought into contact with the positioning pins of the recording drum. Therefore, the positional relationship between the punches holes for printing and the recorded image is held constant without being affected by an undulation or swell on the edge of the printing plate.