Abstract: Based on the modified solar model by considering the attenuation and scattering of the fog, and considering the heat transfer mechanism between fog droplets and target surface in the foggy weather and the radiation and convection heat transfer of the surface, the heat transfer model of the ground target surface in the foggy weather was founded. The influence of fog visibility and wind speed on the target temperature field was analyzed by the heat transfer model. The temperature time variation characteristics of the targets in the typical foggy weather was also analyzed. The result shows that during the appearance of the fog, the smaller the fog visibility, the lower the temperature of the target surface; the higher the wind speed, the lower the temperature of the target surface. So it's very necessary to consider the influence of the fog and wet air during the heat calculation of the ground targets.