In order to ensure the belt conveyor operation reliable and safe, centralized monitoring and control is very necessary. This paper takes the belt conveyor for coal mine as the background, designs the monitoring system based on PLC technology. The system is composed of PLC and touch screen. It is used to control the machine and display running information real-time. The hardware and software of the system station is designed by S7-300 PLC, including the module setting of PLC and its interface wires. After introducing the system design, simulation is made in the software PLCSIM. The simulation results illustrate the effectiveness and correctness of the proposed method.