To address the selection of wavelengths in a multispectral transient temperature measurement system,a set of test system suitable for the inversion of explosion field transient temperatures is developed.Starting from the principle of radiometric temperature measurement,the wavelength at which temperature accuracy is highest determined by analyzing the relationship between temperature and wavelength sensitivity,and verified by combining the Aquila optimizer constraint algorithm with a field test of a candle burning flame.The results show that when the optimal wavelength for each band is selected,the measured temperature error is minimized to within ±2.1%,reducing the error caused by the selection of wavelength.