In this paper the diurnal variations of soil heat flux(G) and net radiation(Rn) are obtained by analyzing the observational data in Lezhi , Sichuan. The results show that Rn and G reach the maximum at about 13:00. The soil moisture and vegetation cover have a great impact on the ratio of soil heat flux to net radiation (G/Rn).The adaptabilities of several widely used models for remote sensing soil heat flux are analyzed using MODIS data. This paper shows that result differences between the remote sensing models are obvious and Bastiaanssen et al.s model is considered to be suitable over hilly land.