PURPOSE: To keep sufficient recording characteristics over a long period of time by forming a data recording medium by providing a recording layer capable of writing and/or reading data by laser on a substrate.

CONSTITUTION: In an optical data recording medium wherein a recording layer is provided to at least the single surface of a substrate, at least one kind of a compound represented by formula I is added to the recording layer. As the substrate, any known substrate transparent to used laser can be arbitrarily formed. As a representative example, glass or plastic is designated. The recording layer is provided as a single layer or two or more layers. The thickness of the recording layer is usually 0.01-lμm, pref., 0.03-0.8μm. In the case of reflection reading, said thickness is especially pref. odd number times l/4 of a laser wavelength used in reading.