Abstract: The high-speed hole detection system for strip steel was developed to meet the urgent needs for detection of hole defects in the strip steel produced by 1420 CDCM mill in Baosteel Co., Ltd. This system, which was designed based on machine vision technology, has been working in the extremely tough conditions for more than 2 years. Configured with transmission illumination and high-speed linear scanning CCD cameras as image sensors, high quality images of steel strip can be obtained in real time, which can be processed at a speed of 30 ms/frame with the detection software. The software transfers the control instructions and hole-detecting results to the server through a C/S network structure that consists of 3 industrial PCs, and a terminal connecting the server computer displays inspection results and sends alarm signals. Due to its stateoftheart design, high-efficiency object detection and edge detection algorithms, the outstanding performance and good reliability of this system have been fully proved in the practice for more than 2 years.