The　Ganhaizi　Bridge　is　a　multi-span　bridge　having　continuous　CFST　truss　girders　and　CFST　composite　piers.　An　FE　model　of　the　bridge　has　been　established　using　the　commercial　program　MIDAS/civil　in　order　to　study　the　elastic　seismic　response　characteristics　of　this　new-type　bridge.　The　analysis　results　demonstrate　that　due　to　the　relatively　light　self-weight　of　the　bridge,　its　fundamental　mode　is　actually　a　longitudinal　mode　having　the　frequency　of　0.204Hz,　which　indicates　a　flexible　bridge　possessing　of　satisfactory　seismic　behavior.　Meanwhile,　the　carrying　capabilities　of　all　the　pier　sections　satisfy　the　seismic　requirement.　And　the　stress　in　the　critical　regions　(such　as　the　bottom　of　the　high　piers,　the　slant　supports　at　the　connections　of　the　beams　and　piers,　and　the　stiffness　variation　sections　at　the　tops　of　the　RC　webs　of　the　composite　piers)　also　satisfies　the　seismic　requirement.　The　concrete　web　plates　at　the　bottoms　of　the　composite　piers　participate　in　the　seismic　motions　of　the　entire　structure,　resulting　in　the　stress　reduction　of　the　pier　tubes　and　thus　improving　the　seismic　performance　of　the　bridge.