Abstract ： Research purposes ： Exploitation of underground large space structures became hotsj^ot in the development process of urbanization in recent years，some seismic codes went into effect in these years，but tlie level of seismic theory and application still have room for improvement compared with ground structures，it ’ s not adaptable with the fast development of underground construction. Based on time history analysis method，this paper simulates and analyzes the subway station which has a overpass bridge on top，result data of 2 conditions which describe the different position of subway station and overpass bridge is analyzed and concluded，hoping it is helj^ful to the recognition and metliod perfection of seismic design of underground structures. Research conclusions:( 1 ) Displacement difference between top plate and bottom plate of the station under all conditions can meet the requirement of the limit of elastic inter - story disj)lacement angle in the relevant codes. (2) Under the condition that deformation and bearing capacity of structure meet t!ie requirements of code，the bridge - station separated plan saves more expenditure and labor cost. ( 3 ) Results of time history analysis of underground constructions should be compared with the corresponding results of other seismic analysis methods and be corrected，the analysis of seismic performance of underground structure should be analyzed qualitatively and taken as reference of structure design. (4) The research results have reference value for the seismic analysis and structural design of underground engineering.