Abstract: Two stiffness and damping of the seal were calculated with the finite element method; the influence of the racetrack and the primary seal ring mass on the stiffness and damping was analyzed; then the vibration process of the seal caused by transient force was analyzed. The results declare that film thickness has a great influence on the stiffness and damping, especially when the thickness is less than 5μm; free vibration frequency of the system is mainly decided by the mass of the seal racetrack, and the effect of the primary seal ring mass on free vibration frequency is neglected; the different ratio of the system mass with the same racetrack mass has a little influence on the convergent time of the vibrating system.