With the initial applications of unmanned aerial vehicle technology in various fields, the infrared (IR) radiation charac-teristics of the UAV become an issue of mutual concern. In this experiment, the radiometric calibration of middle wave and long wave infrared detectors has been done. SR800R 12D_ET extending blackbody made in Israel is used for the radiometric calibration of middle wave and long wave infrared detectors. The quantitative connection between the optical entrance pupil radiation and the output of detector is established, and the responsivity of the infrared detector is obtained. The radiation characteristics of the UAV is measured while flying, and the temperature of UAV target is inverted by using single-band method, dual-band colorimetric method and dual-band method based on black-body calibration.