An image-forming method, containing the steps of: superposing a heat-sensitive transfer sheet on a heat-sensitive transfer image-receiving sheet so that the following receptor layer can be contacted with the following thermal transfer layer; and providing thermal energy in accordance with image signals, thereby to form a thermal transfer image;in which the heat-sensitive transfer image-receiving sheet comprises, on a support, a receptor layer containing a polymer latex, and a heat insulation layer containing hollow polymer particles, and the heat-sensitive transfer sheet comprises, on a support, a thermal transfer layer containing any one of compounds represented by formulas (1) to (7): in which, one of Z1 and Z2 represents ═N— and the other represents ═C(R95)—; Z3 and Z4 each independently represents ═N— or ═C(R96)—; R51 to R114 each independently represent a substituent, or a hydrogen atom or a substituent; n8 to n18 each independently represent an integer of 0 to 5, 0 to 4 or 0 to 2.