Abstract: In order to solve the problems of difficult maintenance and emissivity determination of the traditional stove dome temperature measurement system, a method of dual band log ratio amplification temperature measurement was adopted. After theoretical deduction and experimental verification, the results show that, under the premise of setting the temperature unchanged, the measurement results of this method are almost consistent with the temperature with the change of time. The relationship between the setting temperature and measurement temperature is also verified. The absolute error of temperature measurement is less than 6℃, with high measurement accuracy. It is also verified that the output voltage of LOG112 is linearly related to the reciprocal of the actual temperature and it is consistent with the theoretical deduction. The study combines radiation thermometry with logarithmic amplification, and it is of great significance to solve the existing problems and improve the temperature measurement accuracy of vault.