Airborne High-spectral Interferometer Sounder (HIS) is a detector designed to measure the infrared atmospheric background radiation in nadir viewing mode. Based on HIS infrared high-resolution spectral data, sensitivity analysis of atmospheric temperature and major atmospheric absorbers were carried out. By introducing the concept of information content and using the 1D-VAR method, the ability of detecting atmospheric parameters was analyzed with HIS measurment. The information content, degree of freedom and vertical resolution of temperature and water vapor have been used to characterize the observation system. The information content of temperature and water vapor was 49.5 and 25.2 respectively, the degree of freedom was 10.5 and 5.6 respectively, the average vertical resolution of temperature was 2.2 km, and the average vertical resolution of water vapor was 2 km. The relationship between the inversion accuracy and the instrument noise was discussed. It shows the minimum measurable accuracy of retrieved temperature and humidity profile.