In this paper, a three-stage local binocular BA (bundule adjustment) is proposed based on the ORB-SLAM2 algorithm, which is based on the large value of the initial value and the binocular camera model. In order to reduce the influence of cumulative error on 3D-2D matching in the uniform model, the ring matching mechanism is introduced to eliminate the mismatched again and match the key frame map point with the current frame 3D-2D projection. In the tracking part of the local map optimization phase, the normal frame between the two nearest key frames is also optimized as the local frame when the key phase is inserted into the key frame. KITTI data set experiments show that the three-stage local binocular beam method has more accurate 3D-2D matching compared with ORB-SLAM2, which improves the optimization constraint and improves the motion estimation and optimization precision.