The system utilizes non-contact three-dimensional point cloud reconstruction measurement technology to dynamically and accurately measure the external geometric dimensions of train wheelsets, including tread wear, flange thickness, wheel height, wheel diameter, wheelset inside distance, QR value, and out-of-roundness. Meanwhile, it can accurately identify tread abrasion faults of wheelsets through infrared image stitching technology. The system has strong anti-environmental interference capabilities and adaptability to harsh working conditions, and is suitable for the automatic detection of wheelsets of various types of metro trains.