In　order　to　investigate　the　nonlinear　seismic　responses　of　isolated　bridges　with　lead　rubber　bearings　(LRB)　under　multi-directional　horizontal　earthquake　excitation,　Bouc-Wen　model　of　LRB　under　two　horizontal　orthogonal　directional　excitation　is　adopted.　Based　on　this　model　of　LRB,　an　analytical　model　of　nonlinear　seismic　responses　of　a　continuous　multi-span　isolated　bridge　with　LRB　and　its　solving　method　are　carried　out.　The　multi-degrees-of-freedom　mathematical　model　of　the　seismically　isolated　bridge　is　proved　to　be　right　and　the　bi-directional　coupled　Park　model　of　LRB　is　proved　to　be　reasonable　by　the　shaking　table　tests　of　the　continuous　girder　isolated　bridges　model　with　LRB.　It　should　consider　the　bi-directional　coupled　interaction　of　the　restoring　forces　of　LRB,　which　has　considerable　effects　on　the　seismic　responses　of　the　isolated　bridge.　Vertical　tension　of　LRB　should　be　considered　if　vertical　earthquake　amplitude　is　greater　in　isolator　design.