When a mobile robot performs tasks in an unknown environment, it needs to accurately perceive the map environment and other object positions to determine its own position. In order to improve the global positioning accuracy of mobile robots, a binocular vision global positioning method for mobile robots under laser radar SLAM is proposed. Based on the distance measurement principle of the binocular vision system, any camera in the binocular camera is selected to establish the main coordinate system, and a binocular camera model is constructed. The parameters in the binocular camera are calibrated by combining the chessboard diagram and Zhengyou Zhang calibration method. On this basis, the scale of the feature points in a single frame image is calculated, and the binocular vision initialization is completed. The weight function is used to calculate the weighted value and distance value between any feature point and line or face, estimate the position of the mobile robot and introduce a non iterative distortion compensation method to achieve global positioning of the mobile robot. The test results show that the minimum error between the positioning results of the proposed method and the actual motion position is 0.1 m. This method can accurately locate the position of the mobile robot and guide it to better perform tasks.