An accurate modeling and verification method is proposed to improve the calculation precision of space-based optical scattering characteristics of space objects. Further, a mathematical model is established for space-based optical scattering characteristics using the bidirectional reflectance distribution function via finite element analysis and vector coordinate transformation based on the object background radiation, surface material properties, geometric dimension, and orbit elements. Subsequently, this model is experimentally verified in a low-temperature and vacuum environment using the measurement platform of the optical scattering characteristics; the modeling data agrees well with the measured data, and the mean square errors are lower than 9.57%, demonstrating the validity of the proposed method.