PURPOSE: To easily and safely insulate the heat of a dish at the optimum temperature by connecting thermal elements to a DC power source while sandwiching them between confronted transmission side insulating base plate and radiation side insulating base plate on the lower surface of a plate for placing the dish.

CONSTITUTION: This dish heat insulator is composed of a plate 20, thermal elements 30, radiator 40, waste heat fan 50 and control unit 60 and arranged by making a transmission side insulating base plate 31 of the thermal element closely adhere to the lower surface of the plate 20 and making the radiator 40 closely adhere to the radiation side insulating base plate 32. A temperature sensor 67 connected to a control circuit 65 is fitted while being embedded or closely adhered to the plate 20 and detects the temperature of the plate. Then, the control circuit 65 monitors a change in the resistance value of the temperature sensor 67 and controls the ON/OFF of electrification to the thermal elements 30 so that the temperature of the plate 20 can be settled within the range of the set temperature. Besides, a polarity changeover switch 66 is selected into a heating mode or a cooling mode corresponding to the kind of the dish to be placed on the plate 20 and the direction of electrification from a DC power source to the thermal elements 30 is switched.