This design is based on S7200 series PLC and white high power LED lamp. According to the characteristics of the tunnel, the intelligent lighting control system is designed. The video vehicle detector for detecting vehicle speed and vehicle, brightness detector is mainly used to detect the light intensity, according to the PLC video vehicle detector and brightness detector signal acquisition, after calculation, to the tunnel lamp group (LED lamp group) output brightness command for stepless regulation. The communication mode between PLC and PC is Ethernet. The experimental results show that this design can greatly save tunnel friction power. In theory, the design can be applied to all kinds of light source and the length of the tunnel.