A method of forming an image, containing superposing a heat-sensitive transfer sheet on a heat-sensitive transfer image-receiving sheet, and applying thermal energy from a side of a heat-resistant lubricating layer described below of the heat-sensitive transfer sheet, to form a thermally transferred image,in which the heat-sensitive transfer sheet comprises a substrate, a thermal transfer layer containing a thermally transferable dye and a resin on one face of the substrate, and the heat-resistant lubricating layer on the other face of the substrate; the heat-sensitive transfer image-receiving sheet comprise a support, and a heat insulation layer and a receptor layer on the support in this order; the thermal transfer layer contains a polymer compound having fluorine atom-substituted aliphatic groups on its side chains; and the receptor layer contains a latex polymer having a glass transition temperature of from 20° C. to 60° C.