Site　seismic　analysis　plays　an　important　role　in　the　practical　seismic　design　of　underground　structures,　and　the　equivalent　linear　method　is　a　widely-used　approach　for　the　seismic　response　analysis　of　one-dimensional　soil　layer.　Based　on　the　theory　of　the　equivalent　linear　method,　an　equivalent　linear　method　for　the　seismic　design　of　underground　structures　is　proposed.　And　the　methods　to　calculate　the　material　properties　are　also　presented.　Then　the　proposed　method　is　applied　in　the　transverse　seismic　analysis　of　a　subway　station.　The　Davidenkov　constitutive　model　is　applied　in　the　time　history　method　as　the　comparative　model.　The　error　between　them　can　meet　the　requirements　of　engineering　design.　The　proposed　method　has　advantages　of　the　equivalent　linear　method　and　the　time-history　analysis　method　for　underground　structures,　which　can　be　used　as　a　time-history　analysis　method　for　the　seismic　design　of　the　underground　structures　such　as　subway　stations.　©　2018,　Editorial　Office　of　Chinese　Journal　of　Geotechnical　Engineering.　All　right　reserved.