Thermal inert in method is one of the main approaches for drought monitoring by using remotely sensed data. The method is widely used in the China North Plain which is relatively flat. In our study, we tried to apply the approach to the agricultural areas of Shaanxi Province in the Northwest China with terrain and climate varies. The results showed that apparent thermal inertia can be used to monitor the drought occurrence. Considering the effects of terrains, vegetation coverage and soil types, the more homogeneous the land surface is, the better correlation between the apparent thermal inertia mid surface soil moisture is