An information recording medium is provided that has high recording sensitivity and high erasability, even when a recording layer thereof is as thin as about 3 nm. An information recording medium 15 on which information can be recorded by applying light or electrical energy has at least a recording layer 104 that undergoes phase change, while the recording layer 104 contains at least one element selected from among Zn, Si and C, and Sb in total proportion of 85 atomic % or more and has composition preferably represented by the formula Sb100-a1M1a (atomic %) (wherein M1 represents at least one element selected from among Zn, Si and C, and al is a proportion in term of atomic % that satisfies a relationship of 0