Abstract: In this paper,the polarization characteristic of the particle group scattering based on Mie scattering theory is analyzed, and the correlative experiment is done with two species of particle ball of different diameters(0.26μm,0.55μm). The result shows the polarity of scattering light of the bigger particle in horizontal direction is smaller than the smaller particle. On the contrary, the polarity of scattering light of the bigger particle in vertical direction is bigger than the smaller particle.