The operating wavelength of the uncooled infrared focal plane arrays(uncooled IRFPA) is 8～14 μm. The uncooled IRFPA can obtain a specific wavelength of radiant exitance by adding a specific wavelength filter. Then the colorimetric temperature measurement is used to complete the industrial low temperature measurement. The basic principles of colorimetric temperature measurement of uncooled IRFPA is introduced, the theoretical basis for using the double wavelength colorimetric measurement temperature principle in range of 8～14 μm is discussed in detail, and the MATLAB simulation is used to determine the principle of the best double wavelength selection of the industrial low temperature measurement. Finally, the T－R(T) image of dual wavelength(8.8 μm, 10.6 μm) is simulated, and the results can meet the requirements of the temperature measurement accuracy.