Abstract: A photoelectric thermometer was designed based on the temperature measurement principles of double line of atomic emission spectroscopy, which could be used to measure the transient high temperature in complicated environment. The static constant calibration experiment was conducted, where CuⅠ 510.5nm and CuⅠ 521.8nm were selected from the atomic spectra database as the temperature measurement element spectral lines. In the obtained constant values, A and B were 0.1083 and 628.387, respectively. Cu combustion temperature field was measured by the calibrated photoelectric thermometer. The obtained data was compared with temperatures measured by M5 infrared thermometer calibrated by the metrology department. The results show that the average relative error for the two methods is 1.3%, which provides a theoretical basis for the accurate measurement of transient high temperature by the atomic emission spectroscopy method.