Abstract: Common faults of coal mine conveying belt were analyzed as well as their causes, including splice breaking, longitudinally tearing, sideslipping, coal-water mixture and conny piling up, etc. Existing monitoring technologies for common faults of coal mine conveying belt were summarized as well as their main problems. For the problem that existing monitoring technologies only alarm after faults but cannot pre-alarm, an intelligent detecting and pre-alarming system for coal mine conveying belt was proposed which was based on machine vision.