Abstract: In order to obtain larger camera visual field and higher system robustness,a new binocular device is deve-loped.A stereo vision system based on this binocular device is built and calibrated.In order to eliminate image distortion, an explicit-implicit distortion correction method is presented,which can correct radial and tangential image distortions and can be solved with least square method.A compact and precise step-rotation method is used to rectify the epipolar lines.Experimental results show that the stereo image pairs processed by explicit-implicit distortion correction method and step-rotation method can meet the requirements of stereo matching.