Abstract: Based on the characteristic of light radiation by nuclear explosion, in combination with the atmospheric characteristic in the middle latitude area in China, the atmospheric transmission performance of light radiation at (0.2～1.2)μm wave band was studied. It is found, through the analysis of the actual measured data, that the main compositions in atmosphere to affect the (0.2～1.2)μm light radiation are the molecular absorption and the scattering of steam, carbon dioxide and ozone, as well as the scattering of big aerosol granules. The atmospheric transmission empirical formula for the horizontal transmission of the (0.2～1.2)μm light radiation was improved with these factors. The result of computer simulation indicates that the formula can best describe the atmospheric transmission of the light radiation in middle latitude area in China in the (0.4～0.8)μm visible light wave band. The result of quantitative calculation for (0.4～0.8)μm wave band light radiation was directly used in the nuclear explosion subsystem, which took the visible light radiation to simulate the nuclear explosion. The experimental result indicates that more accurate measurement can be achieved with the atmosphere transmission software.