PURPOSE: To easily recognize a slip and a part, both of which are not yet read, if the slip cannot be read by constituting such that a display means displays the presence or absence of a recorded mark corresponding to its recording position or failure of reading.

CONSTITUTION: A mark reading part 10 start reading. If an action conveying the slip 11 develops en error and a reading failure occurs, the part 10 outputs a read failure detection signal to a CPU 13. Judging from the read results stored in a memory 14, the CPU 13 identifies the presence or absence of the mark in each recording position of the slip 11 and the part which cannot be read. According to the results that the CPU 13 identifies, a display means 16 composes a display picture. If the read failure occurs due to the error regarding the conveyance of the slip 11 in such a way, the read result is image-displayed. The image display shows the presence or absence of the mark in its recording position of the slip 11 and that the part which cannot be read is identified. Consequently the part which is not read and whether the slip 11 has been read or not can be easily decided by recognizing the picture of the display device 16.