The emissivity of natural meterial is a important factor in the interpretation of thermal image. Sometime

the effect of emissivity is quite conspicuous under some specific conditions of environment. However

one does not

pay enough attention to their infuluences in the interpretation of the thermal remote sensing data. In this paper

author proceeded with the thermal radiation law attempts to illustrate this problem by combining the thermal image and temperature measurement data on the ground. Meanwhile

some factors to be closely related to the emissivities have been represented. But

how we can eliminate their effects in the interpretation of thermal image is depended on further study.