Based on the summary for the sea fogs of different areas of China sea, an overall distribution model about its micro-physics structure was put forward and its characteristics for China sea fog was summarized. The scale parameter was calibrated for most common sea fog, the extinction coefficient of different sea fogs were quantitatively analysed according to Mie theory, then, the attenuation coefficient was calculated in accordance with the formulars given by Mie and the final attenuation level was known. After a comparison, it witnessed a good agreement between theoretical calculation and experimental statistics. According to Mie theory, under the condition of salty fog drop, the average extinction coefficient of intermediate infrared radiation under common advection fog was 2.90, the extinction coefficient decreased monotonously along with the increase of scale parameter; while under the condition of pure water, the average extinction coefficient of intermediate infrared radiation was 3.35, the extinction coefficient increased monotonously along with the increase of scale parameter.