The invention provides a single factor atmospheric polarization modeling method based on Rayleigh scattering, comprising the following steps: selecting the observation point and establishing a celestial coordinate system and obtaining the current time sun position using the observation time and observation point geographic coordinate; selecting any point to be measured on the celestial sphere surface and solely determining a northeast coordinate system based on the current time sun position using the point to be measured as the coordinate origin; in the northeast coordinate system, decomposing the incidence natural light into two beams of linearly polarized light in same intensity, vertical electric-field vibration direction, no fixed phase relation, and computing the scattered light electric field strength component under linearly polarized light incidence. The method uses the electric intensity vector to describe light wave and uses the vector size of the scattered light electric field strength component to obtain the polarization degree of the point to be measured and uses the vector direction of the scattered light electric field strength component to obtain the polarization direction of the point to be measured, thus the distributed model of the all-day atmospheric polarization information is obtained and the accuracy and the expansibility of the atmospheric polarization model is increased.