The prestressed steel-reinforced concrete (PSRC) structures are composite prestressed concrete structures for arranging rolled or welded steel sections, mostly applied in large-bay long-span architectural structures such as multi-storey public buildings, bases and tops of tall buildings, garages, etc. The static behaviour of a PSRC structure has been studied worldwide (Xueyu et al. 2011, Jun et al. 2009, Chuanguo et al. 2007), but there are few studies on ductility. The results of a low-cyclic reversed load experiment on four PSRC and SRC simply supported beams (Weichen, 2007) demonstrate that the hysteresis curves of the PSRC beam exhibit a distinct shuttle shape, with good displacement ductility, energy dissipation capacity, and deformation capacity. Liu Bingkang et al. (Bingkang, 2007) conducted an experimental study of two double-span prestressed precast concrete frames which were subjected to a vertical low-cyclic reversed load. This demonstrated that the beam-end sections that resist bending depending only on prestressed reinforcement have plumper hysteresis curves and excellent energy dissipation capacity, without obvious reduction in section bearing capacity when curvature ductility coefficient arrives at 4. Thus, they can meet the requirements of bending moment adjustment. However, there are still no studies of the basic issues of a PSRC frame structure, including ductility under vertical seismic effect, and failure mode in the context of rare earthquake.