To investigate the laws of atmospheric background radiation and instrument radiation as well as control the instrument thermal radiation and instrument accuracy, a measurement system of atmospheric background radiation is designed. The effects of various error sources, such as each component of this measurement system and radiation calibration, on the total measurement error are analyzed. Meanwhile, the factors influencing the accuracy of calibration are also analyzed. Finally, the direction of improving the measurement work is determined. These results show that the measurement error of this system in the calibration region is mainly composed of the radiometric calibration error and random error, whose values are 2.4719% and 0.0790%, respectively. In addition, the composite error is 2.4732%. For most of excellent astronomy sites, the atmospheric radiation intensity is far lower than the calibration value, and thus the extrapolation measurement is unavoidable. The estimation results of the extrapolation measurement errors indicate that the extrapolation measurement can lead to relatively high measurement errors. Therefore, in order to improve the precision of atmospheric background radiation measurement, the standard radiation sources with low radiation intensity are indispensable. The development of the atmospheric background radiation measurement system and the measurement work in the field are helpful to experience accumulation for the further development of large aperture infrared astronomical telescope systems and their practical applications to infrared astronomical observations.