PURPOSE: To prevent incorrect use due to the alteration of an identification card, by scanning owner's own picture such as a sign, a photograph of face, or the like formed on the card, recording the picture signal on a prescribed recording medium and comparing the recorded picture signal with that of the sign, photograph of face or the like obtained by scanning at the use of the card.

CONSTITUTION: At the issue of an identification card 1, a picture recognizing device 25 scans a photograph 3 of face and a sign 5 which specify the owner of the card 1 and a picture signal obtained by said scanning is recorded in a host computer 21 for a terminal device 22 at a window processing the card 1 together with its card number 4. At the use of the card 1, a picture recognizing device 25 scans the photograph 3 of face and the sign 5 of the card 1 through a prescribed scanning line and a picture processor 24 processes the obtained picture signad and applies the processed signal to the computer 21 together with the card number 4 from a keyboard 26. The computer 21 compares the output level of picture signal with the one recorded at the issue of the card 1, and when both the picture signals are dissident with each other, the computer determines the card 1 as incorrect use, preventing the incorrect use of the card 1.