A temperature control system includes a temperature control circuit having a plurality of predetermined temperature values, a switch control circuit and a heating control circuit. The temperature control circuit outputs control signals according to the plurality of predetermined temperature values. The switch control circuit turns on according to the control signals and outputs the DC voltage to the heating control circuit which begins to get hot. The temperature control circuit detects a temperature of the heating control circuit from time to time and turns off the switch control circuit when the temperature of the heating control circuit is equal to a selected predetermined temperature.