An official building is a five floors RC frame structure.Because of the change in architecture functions,a new floor will be added.The added structure is prestressed cable structure.The prestressed cable structure is accounted briefly first,then its different construction periods are simulated by the FEM software.The structural deformation and stress due to different load cases are calculated,so the initial cable stress can be determined.To study this type of structure,one prestressed cable structure is tested for the construction period.Finally,the construction technology of prestressed cable structure is accounted,including the cable prestressing technology,stress monitoring technology.And also the specific equipment for prestressing technology may be a reference for other similar projects.