The expectations of prefabricated buildings are getting higher and higher. The prefabricated rail transit stations and utility tunnels have made great progress. But the design and construction of prefabricated municipal tunnels are seriously lagging behind. The main reasons are the heavy lifting weight of tunnel prefabricated parts, limited clear height of long-distance transportation, many non-standard components and high formwork costs. Therefore, how to realize the lightweight and standardization of the structure is still outstanding and urgent. Taking the interchange project at the intersection of Kaichuang Avenue and Luogang New Town Outer Ring Road as an example, the selection of the structural form of the prefabricated tunnel, the template decomposition method of the structure, the design and application of the prestress of the underground structure, the adjustment method of the horizontal and vertical curve section of the tunnel and the unity of the prefabricated template are analyzed. And the new materials, new products and new processes are applied. The splicing method of ribbed plate structure and wet splicing method is used for the project to make the prefabricated components as lightweight and standardized as possible, and successfully realizes that the cost of the fully prefabricated municipal tunnel is equivalent to that of the cast-in-place tunnel, which provides a certain reference value for the design of the prefabricated municipal tunnel.