In an information recording medium according to the present invention, in which an information recording medium has diffraction grating cells arranged therein, a plurality of types of the diffraction grating cells make up one information recording area. At least one type of the diffraction grating cells included in the diffraction grating cells making up the information recording area are information recording elements, while the other types of the diffraction grating cells included in the diffraction grating cells making up the information recording area are information hiding elements. The information is recorded by two-dimensional arrangement of the diffraction grating cells constituting the information recording elements in the information recording area.