Thyristor valve is a key device of HVDC transmission system, the seismic performance of which can directly affect the seismic safety of the whole DC system, whilst seismic behavior can be an important factor when designing valves. Valves structure used shock absorber design. Based on considering the impact of hinged rotating stiffness, three dimensional finite element models of ideal and improved valves were constructed. Used two procedures in order to calculate the ideal model for mutual authentication their calculation results, and the seismic time history of the system was generated based on the IEEE Recommended Practice for Seismic Design of Substations. First, the dynamic character of two models were calculated. The influencing factors of their dynamic characters were discussed subsequently. Secondly, the response of them were analyzed based upon time history analysis method on horizontal and vertical excitation. The result indicates that the valves had good shock absorbers capacity, and under horizontal seismic, valves may occur oscillation phenomenon at low frequency, and also the improved valve structure model can improve displacement deformation of the valves structure.