Whether the external dimensions of hydraulic components are qualified is directly related to the quality and performance of hydraulic products. Aiming at the problem that the weak texture on the surface of the hydraulic component caused great interference to the measurement, the method of projecting random spots to the target scene was used to enhance the texture of the hydraulic component. A binocular stereo vision system was set up and calibrated by a new circular array calibration plate to obtain the internal and external parameters of the two cameras. The digital images collected by binocular cameras were matched by pixels using the normalized covariance correlation algorithm after the limit constraint to obtain the disparity value and the three-dimensional data of the corresponding positions of the hydraulic components. Results showed that the system can obtain clearer point cloud images, and has a higher recognition rate and better robustness for the measurement of hydraulic components. It can meet the real-time detection of weak texture hydraulic components in assembly line production.