Based on radiosonde dataset from 105 stations in China,NCEP/NCAR reanalysis dataset,ERA reanalysis dataset and JRA reanalysis dataset,a study is performed on the reliability of the annual mean free atmospheric temperature from reanalysis datasets in China by means of linear analysis,standard deviation,correlation coefficient as well as EOF decomposition.Results suggest that:In numerical aspects,three reanalysis datasets are all lower than the observed dataset,and NCEP/NCAR dataset is much closer to the observed dataset in upper troposphere while ERA and JRA datasets are closer in middle and lower troposphere;In terms of annual and interdecadal trend,ERA dataset has higher ability to reproduce those trends in the upper troposphere in north region while NCEP/NCAR dataset is better in the upper troposphere in south region;Three reanalysis datasets have comparable ability in reproducing the trend in middle and lower troposphere;In the aspect of spatial and temporal variation characteristics,NCEP/NCAR and ERA datasets can preferably perform the feature of interdecadal variance while ERA and JRA datasets can reveal the characteristic of annual variance well.