Based on the physical model of which the targets were irradiated through artificial illuminator in normal circumstance, the calculation model of surface temperature was built through building heat conduction differential equations and altering the outedge radiation power. Combing the calculation of surface temperature related to targets′s geographical circumstance and orientation, taking the Hefei building′s eastward surface for example, the surface temperature was simulational calculated and discussed in different irradiation times and illumination parameters. The results show that altering the targets′s outedge namely the targets are irradiated through artificial illuminatorm, the temperature of targets are changed, the degree of variety is determined by illuminator′s power, distance, incident angle, and in general conditions, the surface temperature is changed obviously in the night, but not in the daytime.