In order to realize the accurate calculation of the passing smog distance of laser angle measurement, a smoke model algorithm using discrete expansion ball to simulate smoke diffusion law was proposed innovatively in this paper, which could conveniently calculate the influence law of different crosswind wind speed, ground station location and trajectory planning and other situations on passing smog distance. According to the flight high speed video of a certain missile, the smoke expansion model was revised, and the calculation results of smoke penetration were basically consistent with the actual flight test results, which verified the validity of the algorithm. The research results can be used in weapon systems of radar angle measurement, laser angle measurement, infrared angle measurement and so on.