An optical information recording medium for recording information by a plurality
of record mark lengths, wherein the shortest mark length is at most 0.5 m,
and a crystal state is an unrecorded or erased state and an amorphous state is
a recorded state, wherein the erasing is carried out by recrystallization which
substantially proceeds by crystal growth from an interface between the amorphous
portion or a melt portion and a peripheral crystal portion; and an optical recording
method suitable therefore. The medium of the present invention has characteristics
that overwriting can be made at a high speed, the jitter of mark edge is small,
mark length modulation recording can be made at a high density, and the formed
mark is excellent in the stability with the lapse of time.