There are many defects in the exposed installation of puncture clamp in the lighting wiring of expressway tunnel. The new tunnel lighting cable branch connection scheme and branch components, from connecting devices, seals and shells to the connection between branch line cables and tunnel lamps, are optimized with new ideas, so as to comprehensively improve the connection quality and waterproof capacity, and greatly improve the overall performance. The scheme simplifies the installation process, shortens the construction time, makes the layout of branch joints in the bridge simple and uniform, and provides a strong guarantee for reliable operation in the future.