It is known that there are sparse weather stations on the Tibetan Plateau,and the lack of real soil temperature data affects the understanding of surface thermodynamic structure over the Plateau.Clear sky T_BB data are employed,and the verified clear sky T_BB data in 1998 from May to August through variational techniques by real soil temperature can capture the distribution features of mean soil temperature of the Plateau.It turns out to be a kind of important data source to the central and western Plateau,and plays an important role in the Plateau underlying thermodynamic structure study.