A thermal transfer sheet includes a dye layer disposed on a first surface of a substrate film. The dye layer includes a decolorizable dye. The decolorizable dye has a color difference ΔE*ab between a color A and a color B of 10 or less, where the color A is a color of a transfer-receiving body before the decolorizable dye is transferred to the transfer-receiving body, the color B is a color of a portion of the transfer-receiving body with the decolorizable dye having been transferred thereto, and the color of the portion is a color after the portion is irradiated by a xenon lamp at an irradiation intensity of 1.2 (W/m2) for 50 hours, the portion having a reflection density of 0.5 or greater before being irradiated by the xenon lamp.