Abstarct: baxsed on investigations and literature review, underground structures are safer than surface structures against earthquake. Because surface structures only in their lower level are connected to the ground and could freely vibrate, but underground structures since they are connected to surrounding environment show more resistant to vibration. Before 1995 the underground structures were not designed with taking into account the dynamic loads. Nowadays, with the progress of technology, digging underground spaces is possible in many geological conditions. Considering the ongoing development especially in urban tunneling and underground spaces, it is necessary to be sure about dynamic behavior of these spaces against seismic loads. The aim of this study was to evaluate support system of circular tunnels built in the shallow areas of the city, against seismic loads. In this research as a case study, tunnel of Mashhad Metro Line 2 is analyzed. Since the tunnel located in soft ground environment, surroundings environment of tunnel considered as continuous and numerical analysis was conducted by Flac2D software. Then static modeling was conducted, changes included in the statistical model applied for new boundary conditions, dynamic loading, check the mechanical damping and natural frequency to make model for dynamic analysis. For dynamic tunnel analysis, earthquake load of operation Seismic Design (ODE) and maximize earthquake (MDE) is considered, taking into account various considerations. Site acceleration mapping of soil as a stress history is applied to the model. In order to calibrate dynamic analysis of the relationship between Wang and Penzein analysis was used. That of the results obtained have shown would be a logical correctness. Finally, taking into account all static and dynamic forces and by factors related to levels of seismic design load combination ODE and MDE, system performance was analyzed kept running. Analysis suggests proper operation and designed support system under different loading combination and design levels meets the design objectives and the need to strengthen the support system is not necessary. Safety factor of support system for designed seismic MDE and ODE is obtained respectively 1.3 and 1.1.