An information recording medium comprises at least a substrate, a recording layer which is installed on the substrate via a protection layer and in which the atomic arrangement is changed without the shape thereof being changed when a recording energy beam is irradiated and the optical constants are changed, and a reflection layer reflecting the recording energy beam and by making the information recording medium comprise a material such that the mean composition of the recording layer is expressed by a general expression of A.sub.w Ge.sub.x Te.sub.y Se.sub.z (where symbols w, x, y, and z indicate atomic percent and have the predetermined values and A indicates at least one of the predetermined elements Sb, Cr, Co, In, and Ag, etc.), an information recording medium in which the recording, erasing, and reproducing characteristics are satisfactory and the stability is kept superior for a long period of time can be obtained.