The spacecraft autonomous navigation technique using X-ray pulsars is studied in this paper.It is demonstrated that the position of a spacecraft can be determined based on the pulsar observation which is obtained by comparing the arrival time of a pulsar signal at a spacecraft and the arrival time of the same pulse at the solar system barycenter.The least square(LS) method and the Kalman filter(KF) algorithm are used respectively to fuse the information obtained from the pulsars.The efficiency of the propos...