Abstract: Establishing connecting pipes between main sewer pipes to realize the interconnection of municipal wastewater systems can significantly improve the resilience and safety of the system. Sewer pipe interconnection projects have been carried out in China; however, the key points of planning and design need to be further studied. By combing relevant cases of pipe interconnection at home and abroad, the design principles and key points of sewer network interconnection were studied, including planning surplus capacity for wastewater treatment plants, determining the excess capacity of sewage wastewater treatment plants, designing integrated pumping stations, determining the location of connecting points, constructing the connecting pipe by pipe jacking and shield, and improving maintenance of the connecting pipes. Furthermore, a case study of the wastewater system planning of a city was used to explain the application scenario of sewer network interconnection in detail. This paper can provide a reference for the implementation of sewer network interconnection in the future.