A three Field of View(FOV) celestial positioning and orientation system was established to achieve high-precision position and orientation.The concept of the three FOV celestial positioning and orientation was described,and the working principles of the system were introduced.A celestial positioning and orientation algorithm based on the minimum loss function was proposed to calculate the geographic position and the azimuth angle information of a carrier simultaneously.According to the structure characteristics of the three FOV system and traditional single FOV system,the advantages of the former on positioning and orientation performance were analyzed theoretically.Finally,the simulation analysis was performed on the effects of the dip angle errors of a carrier platform and the single star measuring errors of a star sensor on the celestial positioning and orientation,and a field experiment was executed with a prototype.Experimental results indicate that the positioning accuracy is 151.624 0 m,the orientation accuracy is 4.630 4″ and the positioning and orientation result is stable.These results satisfy the requirements of the high-precision celestial positioning and orientation.