In order to improve the ground pixel resolution, the image motion compensation device system should be designed to compensate image motion of the CCD plane in the area scan color CCD camera. An image motion compensation mechanism is designed based on analysis of several kinds of image motion compensation methods and discussion on image motion compensation device. Constant-diameter conjugate cam is used to translate the rotation to the line movement. It has the advantages of simple transmission chain and microscopic operation and can reduce the transmission error effectively. The factors that affect the accuracy of image motion compensation are studied and equivalent residual image motions of the compensating system are measured. The measuring results show that the focusing mechanism has a high precision and the error is less than 600 μm/s. Clear color imagine in aerial tests proves that the camera’s technical parameters can meet using demands.