PURPOSE: To exactly grasp a color temperature of a substance whose temperature is measured, by comparing a light beam radiated from a substance to be measured, with a light beam radiated from a standard electric lamp, by relation of a color temperature, and measuring a temperature.

CONSTITUTION: A light beam radiated from a substance 1 whose temperature is measured is led to optical fibers 3, 3' through 2 kinds of filters 11, 12 whose passing wavelength is different, and the first and second 2 electric signals corresponding to intensity of different waveform components are obtained through a photoelectric converting element 4. Also, different waveform components in a light beam radiated from a standard electric lamp 5 are obtained through the filters 11, 12, by which the third and fourth 2 electric signals are obtained. Also, the ratio of the first and second electric signals is obtained by the first calculating circuit 25, and the ratio of the third and fourth electric signals is obtained by the second dividing circuit 26. Also, this color pyrometer is provided with a current source 28 for controlling an electrifying current to the standard electric lamp 5 in accordance with a difference between both outputs of the dividing circuits 25, 26, and an ammeter 29 being an indicator for indicating the electrifying current of the standard electric lamp.