Belt conveyor is widely used in industrial production equipment, its stable operation is an important guarantee for safe and efficient production. Aiming at the problems of low efficiency, high cost and late detection of abnormalities in manual inspection of belt conveyors, taking No.1 belt conveyor in boiler workshop of coal-fired power plant of Zhaofeng Alumina Company as an example, an online monitoring system of belt conveyor is designed to monitor the operation status of belt conveyor in real time. The practice shows that the designed online monitoring system has good application effect, reduces the frequency of serious fault maintenance of equipment, shortens the daily maintenance time, and improves the operation efficiency of equipment. The inspection personnel were reduced from 3 people per shift to 1 person per shift, and the labor intensity was also significantly reduced.