The supportstructure integral piperoofing preconstruction method is new for underground works. The core idea of the method, permanent structure of metro station goes first and then fullface soil excavation, is different from the traditional one. The key technologies of the method include longdistance jacking of largediameter steel pipe, spatial cutting and welding of pipe roof and construction of reinforced concrete structure in small space. The practice shows that the method, which integrates reinforcement, support and main structure, can reduce the excavation and support process and temporary support, control the ground defromation effectively and guarantee good working environment.