For supplying space object detection and recognition with reference data,space object optical scattering characteristics model is established using TracePro.Combining with structure,material,background and orbit,the optical scattering characteristics of the space-based infrared system is simulated by creating solid model,defining material,defining light source and tracing rays in TracePro.The simulation results show that the object spectral irradiance is coincident with that of the sun.The object equivalent reflectivity is coincident with that of the GaAs in specular direction.As the object rotates,the object equivalent reflectivity turns to agree with that of the cladding material,and then keeps stable.The research could provide reference idea for the next work.