The non-linear seismic response behavior of concrete filled in steel tube(CFST) arch bridge subjected to synchronous seismic excition and multi-support seismic excitation is studied in this paper.The non-linear seismic response of CFST arch bridge is calculated by time-history analysis method,and the effect of geometric nonlinear to long-span CFST arch bridge is studied.The influence of internal-force and deformence under dead-load,multi-support seismic excitation,etc to nonlinear seismic response behavior of CFST arch bridge is analysed.The result show that the effect of geometric nonlinear to long-span CFST arch bridge is obvious.