This paper set up a finite element model for tunnel structures by introducing visco-elastic boundary. Through comparing the obtained result with that of centrifuge shaking table model test, the rationality of this method was verified. Moreover, a three-dimensional finite element dynamic tunnel structure model was used to study dynamic interaction of double line tunnel and existing tunnel under seismic load. More attention was paid to the influence of construction reinforcement measures, the installation of purification equipment and deformation joint of tunnel segments on seismic performance of a double-track tunnel. It can be concluded that the interaction between tunnels decreases with the increase of space; construction reinforcement measures evidently reduce the dynamic response of tunnel structure; purification equipment has no clear impact on earthquake response of tunnel structure.