Aiming at the key problems of precise positioning and measurement of objects or objects in scenes,this paper designs a measurement system based on binocular stereo vision and open source co mputer vision library (OpenCV).This project aims to achieve real-time posi tioning of the target.The system calibrates 5million industrial CCD cameras with the method provided by OpenCV.Then the calibration data is used to calibrate the target images which are used to achieve regional segmentation imag es.The distortion caused by the lens process can be removed by calibration.Image parameters can also be consistent.We use the seg mentation algorithm to identify the target in the image.Finally,we get the target coordinates from segmentation data,with whic h the camera′s spatial attitude can be calculated through the camera geometry.The results show the system has superior comprehens ive properties.The experimental measurements show that the results are excellent in the range of 1.4－1.6m.Resp onse time is less than 350ms,distance error is less than 10mm and transverse error is less than 2mm. The test results meet the requirement of the project indicators.