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The weather and climate of the Qinghai-Xizang Plateau （QXP） not only exert profound influences on Asian regional climate but also regulate broader Northern Hemisphere climate patterns.Various global atmospheric reanalysis datasets developed abroad have been extensively utilized to characterize the QXP's climate features.In 2020， the China Meteorological Administration released its first-generation global atmospheric reanalysis product （CRA）， which demonstrated superior performance in regions with dense conventional observations， yet its skill over the QXP remains unclear.In this study， we performed an independent evaluation of CRA's upper-air temperature， wind fields， and relative humidity using 686 high-quality， non-assimilated radiosonde profiles from five stations collected during June-August 2014 in the 3rd Qinghai-Xizang Plateau Atmospheric Scientific Experiment.A non-independent assessment was also performed using routine observations from 21 sounding stations across the QXP and adjacent areas.Results were compared with those from ERA-Interim， ERA5， and JRA-55 reanalysis datasets.Non-independent validation results demonstrate that in the troposphere and lower stratosphere， correlation coefficients of temperature and wind speed between CRA and operational radiosonde observations exceed 0.9.Relative to operational radiosondes， CRA temperature bias of 400 hPa and 500 hPa approaching 0 ℃.The near-surface zonal wind RMSE of CRA is about 2.5 m·s-1， decreasing gradually with altitude to 1.5 m·s-1 at 100 hPa.Relative humidity RMSE remains below 20% across all altitude layers.Independent validation results indicate that errors in air temperature and wind speed over the eastern Qinghai-Xizang Plateau are generally smaller than those over the western plateau， whereas relative humidity errors are larger in the east.From 600 hPa to 30 hPa， the mean root-mean-square errors （RMSE） of CRA relative to radiosonde for temperature， zonal wind， and meridional wind are 1.38 ℃， 3.19 m·s-1， and 3.22 m·s-1 in the western Qinghai-Xizang Plateau， respectively； and 1.16 ℃， 2.65 m·s-1， and 2.90 m·s-1 in the eastern Qinghai-Xizang Plateau， respectively.Errors in the western QXP were slightly larger than in the east and exhibited pronounced diurnal variability.Maximum temperature and relative humidity errors below 600 hPa occur in the afternoon.At 500 hPa， peak relative humidity errors appear in the evening.CRA objectively reproduces the QXP’s vertical structures of temperature， wind speed， and relative humidity.Compared to other reanalysis products， CRA’s relative humidity estimates were closest to radiosonde observations， and wind field errors were slightly higher than those of other datasets but did not exceed 0.4 m·s-1 on average.