This study investigates the effect of aerosol on the polarization distribution of the atmosphere. The polarization distribution patterns under different aerosol conditions are simulated and studied based on the vector radiation transmission mode of the Monte Carlo method. An image-based test system is used to test the polarization pattern under an actual atmospheric condition. The effect of aerosol mass concentration on the polarization pattern is analyzed. The results reveal that with the increase of aerosol mass concentration, the degree of polarization decreases, indicating that the aerosol mass concentration considerably affects the degree of polarization. When the mass concentration of PM10 increases from 27 μg/m ³ to 53 μg/m ³ and then to 103 μg/m ³ and that of PM2.5 increases from 9 μg/m ³ to 28 μg/m ³ and then to 66 μg/m ³, the maximum degree of polarization decreases by an average of 25%. In contrast, aerosol slightly affects the angle of polarization, and thus the distribution of polarization angle is stable.