Based on ERA40 and NCEPI (NCEP/NCAR version I) reanalysis datasets， the upperair observation datasets over the QinghaiXizang Plateau， and the data from the first Tibetan Plateau field experiment in 1979， the characteristics of geopotential heights over the QinghaiXizang Plateau are compared. Although there are some similarities， sensible differences among several reanalysis datasets are found. Comparatively speaking， the deviation of NCEPI reanalysis datasets from upperair observation datasets is the smallest， while that of ERA40 reanalysis datasets is the smallest over 200 hPa from 1980 to 1990 in the northern Plateau. Except that NCEPI reanalysis datasets are in better agreement with the upperair observation datasets over 200 hPa from 1980 to 1990， ERA40 reanalysis datasets are probably closer to reality on the interdecadal timescale in the central and southern Plateau. ERA40 reanalysis datasets show a better spatial similarity to the data from the first Tibetan Plateau field experiment than NCEPI reanalysis datasets．