The present invention provides a heat-sensitive recording material
including a support having disposed thereon a heat-sensitive recording
layer containing microcapsules in which an electron-donating dye
precursor is encapsulated and outside which an electron-accepting
compound is present, the electron-donating dye precursor being capable of
reacting with the electron-accepting compound to develop color, wherein
the microcapsules include at least two kinds of microcapsules having
mutually different volume average particle diameters or different glass
transition temperatures. A difference between each of the glass
transition temperatures of the at least two microcapsules having
different glass transition temperatures is preferably in a range from
20.degree. C. to 70.degree. C. According to the invention, a
heat-sensitive recording material, which is superior in the reproduction
of the gradation of an image and enables recording at high density, is
obtained.