A heating device includes a heater, a safety device, and a holder. The safety device has a heat-sensitive surface facing the heater. The safety device cuts off power supply to the heater in response to reaching a temperature of the heat-sensitive surface to be equal to or higher than a predetermined temperature. The holder holds the heater. The holder has a through hole that opens toward the heater and includes a step portion disposed on an inner circumferential surface of the through hole. The step portion supports an end of the heat-sensitive surface such that a central portion of the heat-sensitive surface of the safety device is not in contact with the heater.