Algorithms for stochastic simulation of a polarized signal arriving at a photodetector of an aircraft laser navigation system are developed. The angular distributions of Stokes parameters of radiation recorded by the detector are estimated by a Monte Carlo method; the effect of different-order scattering on the total recorded signal and polarization degree is analyzed. The signal intensity is calculated with the use of linear polarization filters. The suggested algorithms enable estimating the efficiency of the laser navigation system taking into account radiation polarization under different weather conditions and a possibility of enhancing signal contrast by using the polarization filters.