The reversible thermosensitive recording medium according to the present
invention comprises a support, a thermosensitive layer and a protective
layer in order, the thermosensitive layer comprises an electron-donating
coloring compound and an electron-accepting compound and reversibly
changes the color depending on temperatures, and the protective layer
comprises a reactive heterocyclic compound, and inorganic fine particles
of which surface is at least partially treated into hydrophobic,
alternatively the protective layer comprises inorganic fine particles of
which number-average particle size is 100 nm or less and of which surface
is at least partially coated with organic silane compounds.