An information recording medium superior in recording and reproduction characteristics and capable of use in hostile environments. The information recording medium comprises a substrate, on which are provided a recording layer that is responsive to a recording beam to undergo a change in the sequence of atoms, and a protective layer of insulator in contact with the recording layer. The opposite sides of the interface between the recording layer and the protective layer have different nitrogen contents. The rate of change in nitrogen content near the interface ranges from 1 atomic percent/nm to 50 atomic percent/nm in the direction perpendicular to the interface.
