Galongla tunnel, which is a key project of Zha-Mo highway, is located in highly seismic region. On basis of the seismic evaluation reports of the tunnel and the geological prospecting data, the authors make analysis on the transient dynamic response of the tunnel lining in fault region by means of Newmark's stepbystep implicit integration FEM method and artificial viscousspring boundaries. By means of calculation, the authors obtain the diachronic displacement curves of the crown, arch waist, arch foot and the central part of the invert. Furthermore, the authors assess the stability of the tunnel on basis of the displacement. The calculation results demonstrate that the increase of the internal force of the lining in earthquake is limited with the maximal increase being approximate 8.73%.