In dynamic temperature testing, the colorimetric temperature measurement method effectively reduces emissivity-related influences due to its unique temperature measurement principle, offering advantages such as fast response, wide temperature range, and non-intrusiveness. This study leverages colorimetric temperature measurement to design a dynamic temperature testing device. A comprehensive discussion is provided on the colorimetric temperature measurement principle, device configuration, dual-wavelength selection criteria, and photodetector circuit design. The device underwent static calibration using a high-temperature blackbody furnace, yielding a fitting equation between output voltage and corresponding temperature. To assess measurement accuracy, a hydrogen-oxygen water welding machine heated a stainless steel target to simulate a temperature field, and dynamic temperature measurements were simultaneously conducted using the calibrated device and a standard infrared thermometer. Experimental results indicate that the relative error of the colorimetric temperature measurement device remains below 5.4% within the 400?1200 ℃ range, demonstrating accurate dynamic temperature testing capabilities in this range.