An imaging system in a start camera with higher detection ability and faster data updata frequency was designed based on a Electron Multiplying CCD (EMCCD).To meet the performance requirements of the space navigation for star cameras,EMCCD technologies were discussed in theoretical and engineering aspects.Then,the working principle of EMCCD and its SNR were analyzed.Based on TC285 EM CCD, a design scheme for the star camera was described and the CCD driving circuit,TV signal procesing circuit and a timing controller in the camera were given.Furthermore,the camera performance was verified by simulation and experimental methods and its applications were analyzed primarily.By analyzing the experimental images, it is concluded that the camera can detect the Mv6 stars in the integration time of 8 ms,and its image data updata frequency can reach 10 frame/s.These results meet the rapid imaging requirements in short integration time.