The invention relates to the field of computer simulation, in particular to a radiation effect calculation method in hyperspectral simulation. The method comprises the following steps that parametersrelated to radiation in a scene are determined; self radiation of a target is calculated according to the self surface temperature of the target; reflection of the target to solar radiation is calculated according to solar parameters and the target surface reflectivity; reflection of the target to self radiation of an adjacent building is calculated; reflection of the target to radiation of the adjacent building to solar radiation is calculated; and the radiation effect of the target is calculated according to the solar parameters and atmospheric environment parameters. According to the method, the radiation effect of the adjacent object on the target in hyperspectral simulation can be effectively processed, and the simulation fidelity is improved.