A visible light image simulation method for space-based observation of space target is presented.The speed and position information of the observation platform and the target is generated by the STK,and the imaging process is implemented by Matlab programming.The superiority of this method is to use the visual function of STK,and the orbital parameters of the observation platform and target can be controlled to make the target enter the FOV of camera.Matlab has a powerful image processing library,which can add all kinds of noises and effects to the image during sequence image generation to make the image more realistic.The generated simulation images are mainly used for research on space target detection algorithm.Finally,the motion properties of space target and the stars in simulation image are analyzed,which provides a basis for improving the performance of space target detection algorithm.