Abstract: A new method to rectify the optical axis based on visual servoing is given in this paper. This method separates the linear distortion from the non-linear distortion. Firstly, the non-linear distortion is removed through iterations on the basis of the non-linear distortion coefficients obtained by accurately calibrating camera with many pattern images. Then the position of the camera is finely adjusted by a way of feedback elements according to the linear distortion without special guiding equipment. With the help of this method, finally the problem of rectification of optical axis is perfectly solved.