To provide a temperature measurement system that can contribute to improvement in temperature measurement accuracy of a measurement object.SOLUTION: A temperature measurement system 10 comprises: a light reception unit 21 that receives radiation light radiated from a measurement object 110; a luminance detection unit 22 that detects luminance in the radiation light of a wavelength corresponding to at least one of a visible light ray or a near infrared ray of the radiation light received by the light reception unit 21; a histogram creation unit that creates a histogram of a gradation and luminance of the radiation light on the basis of the luminance detected by the luminance detection unit 22; a representative luminance detection unit that detects representative luminance from the histogram created by the histogram creation unit; and a temperature calculation unit that calculates a temperature of the measurement object 110 on the basis of the luminance detected by the representative luminance detection unit.SELECTED DRAWING: Figure 1