Planetary boundary layer height (PBLH) plays an important role in turbulent mixing,convective activity, cloud formation,atmospheric pollutant diffusion and cloud /aerosol crimping. It is also the basic parameter for the study of atmospheric boundary layer,as well as important parameter for weather,climate and air quality modeling. Currently,radiosonde is the most widely used method for obtaining the planetary boundary layer temperature and humidity profile. However,most sites only launch the radiosonde twice a day (usually at 08: 00 and 20: 00,Beijing time) ,and these sites are inhomogeneously distributed. It is still very difficult to obtain the information on vertical profiles of temperature,humidity and planetary boundary layer height in areas where observations are sparse. In this study,the applicability of the temperature and relative humidity profile from the Atmospheric Infrared Sounder (AIRS) which have a global coverage and the feasibility of using AIRS temperature profile to determine the planetary boundary layer height over the Loess Plateau area were evaluated using radiosonde observation data obtained during the intensive observation periods in summer of 2012 2016. The results indicated that the correlation among the planetary boundary layer heights determined by six different methods are significant. The height differences among various methods are generally not more than 200 m,and the selection of critical Richardson number value has little influence on the determined planetary boundary layer height. On the other hand,AIRS retrieval products can well reflect the vertical variations in atmospheric temperature and moisture,with mean bias and root mean square error less than 1 K and 2 K for air temperature and they are not more than 10% and 20% for relative humidity,respectively. However,the error of surface air temperature between AIRS and radiosonde observation is relatively large,with the mean bias and the root mean square error being-1.68 K and 3.32 K respectively,which could affect the determination of the planetary boundary layer height. The comparison of planetary boundary layer height determined by using temperature profiles from the AIRS with that determined by using radiosonde through Parcel method shows that although the planetary boundary layer heights determined by AIRS temperature profiles are lower than that determined by radiosonde observations,it can reproduce the change of the planetary boundary layer height well. AIRS retrieval temperature profiles can be used to estimate planetary boundary layer height in the study area when radiosonde data are not available. The study will help enhancing the understanding of the planetary boundary layer over the Loess Plateau and provide modelers with information on planetary boundary layer characteristics that can be used to improve numerical model simulations.