The characteristics of infrared and visible signature of satellite depend on the situations of solar radiation in space, which is closely associated with the mode of motion and attitude determination of satellite. In the process of modeling optical signature of satellite in visible spectral band on first principles, optical signature is computed according to geometry relationship among satellite, sun, earth, sensor and optical properties of materials on satellite surfaces. Attitudes change of satellite is analyzed via mathematical description of sense of orientation to sun of solar vanes in proceeding orbit determination and ordinate transformation. The Sandford-Robertson model is then employed to calculate the Bidirectional Reflection Distribution Function (BRDF) which characterizes optical proprieties of materials on the surfaces of satellite, and formulae for calculating infrared and visible signature of satellite including direct and indirect reflections are subsequently deduced. Moreover, Elements of sun-synchronous orbit are used in simulation of optical signature of prototype satellite, and contours of radiation intensity are achieved as well as sequential gray scale pictures of radiance of satellite. Finally, characteristics of infrared and optical signature of satellite are analyzed.