PURPOSE: To securely discriminate the object and to provide the discrimination system for an object which is hardly analyzed and forged.

CONSTITUTION: A discrimination area 3 consists of a true discrimination part 30 formed of a diffraction grating or hologram having characteristic diffraction characteristic and a dummy discrimination part 3b consisting of one or ≥2 kinds of diffraction grating or hologram having diffraction characteristics from said characteristic diffraction characteristics, and only the true discrimination part 3a is optically discriminated by a reader writer; and it becomes difficult for then an illegal forging person to discriminate between the true discrimination part 3a and false discrimination part 3a and specify the true discrimination part 3a, so that its forging becomes extremely difficult.