The light scattering characteristics of graphite microsphere particles are analyzed in theory and calculated numerically by using Mie's scattering theory.The relation of the extinction characteristics with the incident wavelength and particle radius,the relation of the scattering intensity with the scattering angle and the relation of the scattering intensity with the parameter x are obtained.The results show that the less the particle radius is,the better the extinction effectiveness is;the shorter the incident wavelength is,the greater the forward scattering intensity of the particle is.Therefore,the radius of a microsphere can be determined through the measurement of the distribution of the forward scattering light.