In a phase change optical recording medium, by determining heat conductivity relatively higher in one of interference layers on and under the recording layer, heat absorbed into the recording layer can be released moderately through an interference layer. Thereby, cross erasure caused by heating of adjacent tracks can be prevented, and at the same time, excessive heat radiation is prevented from a part of the recording layer nearer to the substrate to thereby maintain appropriate heat in the recording layer. As a result, cross-erasure is prevented, and data can be rewritten with the supply of typical recording/erasure power.