A meshed triple-girder finite element model was adopted for the seismic responses analysis of a cable-stayed bridge located in Hainan province.The linear and non-linear seismic analysis was carried out by employing the response spectrum method and non-linear time history analysis method respectively.The calculating results show that the rigidity of cable towers and main girder can meet the seismic resistance requirement.The elastic constrains and dampers in the longitudinal direction of the main girder can make some limitation of the displacement which happens in the same direction.However

there still exists potential dynamic instability of the main girder.So the displacement of the main girder should be further limited in order to improve the seismic resistance capacity of the whole structure.