In a thermal development method for generating a image from a latent image recorded on an image formation layer of a photosensitive photothermographic recording material, by means of heating the recording material, a first surface, which is one surface of the recording material, and a second surface, which is the remaining surface of the same, are heated; and wherein a second total amount of heat applied to one surface of the first and second surfaces, the one surface being on the side of one unit having a higher heat conductivity of first and second heating units, is controlled so as to be a value of 80 or less when a first amount of heat applied to the other surface is taken as 100, wherein the first and second amounts of heat are total amounts of heat applied to the image formation layer from the first and second surfaces, respectively.