To provide a method and a device for controlling the temperature of a furnace work inside a vulcanizing furnace, capable of measuring the temperature of the work inside the vulcanizing furnace without contact and vulcanizing the work always appropriately, regardless of the volume of the work, by controlling the temperature of the furnace work within an appropriate range.

The temperature of the work inside the vulcanizing furnace heated by irradiation of microwaves is measured, and the measured value is compared with the previously set upper limit value and lower limit value of the temperature of the work. Then, by increasing or reducing the quantity of irradiation of microwaves based on the comparison, the temperature of the furnace work is controlled within the previously set range of temperature.