Abstract: Image motion model on star sensor is an important component of dynamic simulation algorithm of stars, and it lays the foundation for motion blur modeling simulation of high resolution star sensor. Firstly, with the help of the normal distribution of static star image energy model, introducing the star image motion speed, the energy distribution function of moving stars was obtained. Secondly, in order to obtain the star image motion speed, two solution methods were studied: (1) star image motion model based on the coordinate transformation, (2) image motion model based on the stellar rotation vector. Finally, the simulation environment was established. Through adjusting input parameters such as integral time, rate of change of three attitude angle, the launch time, location, important simulation data of stars observed by star sensor in orbit could quickly be obtained, such as navigation stars information, value and direction of image motion, intensity distribution, signal to noise ratio. This work is very important to study and evaluate the star image motion compensation algorithm.