A diffraction grating recording medium (3) that enhances the ability to prevent forgery and make security more reliable. The diffraction grating recording medium (3) comprises a first recording region (31) including viewing image unit cells (11a), (12a), (13a) having a light diffraction structure, and a second recording region (32) including hidden image unit cells (2a). The viewing image unit cells of the first recording region (31) has a grating pitch more than the wavelength of visible light, and the hidden image unit cells of the second recording region (32) has a grating pitch less than the wavelength of visible light.