This　paper　takes　an　actual　station　of　Nanjing　Metro　Line　2　as　the　research　object　and　establishes　the　corresponding　2D　and　3D　overall　time-domain　nonlinear　finite　element　models,　respectively.　By　analyzing　the　results　of　the　two　models,　the　influence　of　the　3D　spatial　effects　of　the　underground　structure　on　the　seismic　response　of　the　structure　is　studied.　The　results　show　that　the　2D　model　cannot　correctly　reflect　the　deformation　characteristics　of　the　3D　station　structure　at　the　middle　of　the　longitudinal　length.　The　results　obtained　from　the　2D　model　are　roughly　equivalent　to　the　results　at　1/4　of　the　longitudinal　length　of　the　3D　station　structure.　The　overall　longitudinal　bending　deflection　of　the　station＇s　top　and　middle　slabs　in　their　own　plane　can　well　reflect　the　3D　cooperative　work　degree　of　the　station.　Based　on　this,　the　conversion　coefficient　of　the　maximum　interstory　displacement　angle　proposed　in　this　paper　can　better　convert　the　2D　model　results.　The　minimum　error　between　the　converted　2D　model　results　and　the　3D　model　results　is　only　0.78%,　and　the　maximum　error　is　only　about　10%.　The　maximum　inter-story　displacement　angle　conversion　coefficient　with　95%　probability　guarantee　finally　given　is　1.447.　Through　the　statistical　analysis　of　the　internal　force　ratio　of　the　3D　model　and　the　2D　model　at　the　key　cross-sections,　this　paper　also　gives　the　conversion　coefficients　with　95%　probability　guarantee　for　the　bending　moment,　the　axial　force　and　the　shear　force　of　the　key　cross-sections,　which　are　0.696,　0.773,　and　0.785,　respectively.