The　seismic　response　of　a　cable-stayed　bridge　is　greatly　influenced　by　the　structural　system.　Previous　studies　show　that　a　proper　elastic　connection　between　the　tower　and　girder　can　improve　the　seismic　behavior　of　a　cable-stayed　bridge.　However,　the　conclusions　are　limited　by　ignoring　the　influence　of　different　heights　of　gravity　centers　on　a　tower-girder　elastic　connecting　device’s　damping　effect　in　a　cable-stayed　bridge.　In　the　proposed　study,　the　influence　is　considered　systematically　by　taking　a　certain　cable-stayed　bridge　as　the　model　and　changing　the　height　of　the　gravity　center　of　the　lower　tower.　The　result　indicates　that　when　the　height　of　the　gravity　center　is　low,　setting　up　an　elastic　connection　between　the　tower　and　girder　will　improve　the　seismic　behavior　of　the　cable-stayed　bridge　effectively.　When　the　height　of　gravity　center　reaches　a　certain　extent,　setting　up　an　elastic　connection　will　increase　the　seismic　displacement　response　instead　of　reducing　the　seismic　response　of　internal　force.　©　2016　Taylor　&　Francis　Group,　London.