Abstract: This paper presents the image oscillation of CBERS 02 CCD camera in ground test and its effect on image quality, and the reason oscillation is due to the vibration of the side viewing mirror. The vibration mechanism is discussed as follow: the spring of the worm wheel elasticity and the worn spring forms a integrate spring and becomes a resonant system. In resonant condition, the outside disturb will be magnified. Thus the method for decreasing or overcoming vibration of the mirror is got. Besides, in orbital condition the camera image quality are fine. It shows that the vibration of the mirror has been overcomed, which explains that the vibration of the mirror does not increase in microgravity.