Abstract: A steering wheel-heating system may include an ambient sensor detecting temperature of external air, an incar sensor detecting temperature of internal air of a vehicle, a water temperature sensor detecting temperature of engine cooling water, a temperature switch receiving FATC-set (Full Auto Temperature Control) temperature, and a controller supplying or cutting power supplied to heating wires in a steering wheel on the basis of the temperature of the external air detected by the ambient sensor, the temperature of the internal air detected by the incar sensor, the temperature of the engine cooling water detected by the water temperature sensor, and the FATC-set temperature.