Abstract: In this paper, the spectral radiation energy of the direct solar radiation and its daily and monthly variations in eastern Tibet during the growing season for crop are discussed.The total radiation, as well as the relative and absolute fluxes of ultraviolet and visual radiations, is strong in Tibet plateau as compared with that in the plain of East China. However, the fluxes of infra-red radiation of the plateau are smaller than those of the plain.According to analysis of the pysiological radiation, some results are useful to explain wheat and the other crops' high products.