In order to investigate the influence of the defects of the optical component on the scattering characteristics, the values of the Mie scattering of a single defect in different size have been calculated based on Mie scattering theory. On this basis, according to the national testing standard of defect levels, the BSDF curve of the optical component under different level of defects has been simulated by using the statistical model of the defect distribution of the optical component. Furthermore, the influence of the different defect level of the optical component and the wavelength of the incident light on the scattering characteristics has also been discussed. The results indicate that, for the given incident wavelength, the value of the Mie scattering increases with the increasing of the size of a single defect and the number of defects on the surface of the optical component. Moreover, for the given wavelength of the incident light, the scattering light energy concentrates with the decreasing of the incident wavelength and the increasing of the level of the defects. The results obtained in this paper can provide valuable reference for the analysis of the scattering characteristics of the optical component surface and the defect tolerance of the optical component.