Abstract: Star identification algorithm is necessary for autonomous attitude determination systems of spacecraft.Being the input of the algorithm,the star pictures imaged by CCD on a star sensor are indispensable for the software debugging,for ground experiments as well as for the evaluation of various star identification algorithms.This paper presents a method of CCD sky map simulation for star sensors,which includes the following procedures:extraction of the observed stars,transformation of position coordinates and grey ness normalization according to CCD camera's parameters,and acquirement of the simulated star pictures.The method has been showed to be feasible by using star identification algorithms.