Constellation Observing System for Meteorology Ionosphere and Climate (COSMIC) provides a new approach to remote sensing the atmospheric profile for areas difficult to periodically measure. Comparing the vertical profile of atmospheric temperature and water vapor derived from COSMIC and Atmospheric InfraRed Sounder (AIRS) retrievals with the collocated European Center of Medium-range Weather Forecasts (ECMWF) and National Centers for Environmental Prediction (NCEP) reanalysis values and radiosonde observations is described in detail in this paper. The results show that the retrievals derived from COSMIC with the feature of global covering, high precision and vertical resolution, low consuming, quasi-real time and all-weather measurement are more close to radiosonde observations relative to AIRS retrievals, at the same time COSMIC retrievals can provide the atmospheric profile structure more detail. The COSMIC shortcoming is the detect height be limited by occultation observation, so it cannot acquire the atmospheric information of low sky. Though AIRS has the better retrieval precision in clear sky it still cannot be used to detect cloudy conditions.