Baihua　Viaduct　which　is　an　important　transportation　project　of　213　National　Highway　was　severely　destroyed　during　the　512　Wenchuan　earthquake.　The　fifth　segment　of　the　bridge　suffered　the　most　severe　unrepairable　damage,　such　as　the　rupture　of　the　piers　and　falling　of　beams.　It　is　worth　to　study　the　performance　through　the　FEM　dynamical　analysis　to　explain　the　damage　performance　of　Baihua　Viaduct　in　the　earthquake.　The　dynamical　FE　model　of　the　Baihua　Viaduct　is　established　considering　the　non-liner　properties　of　piers　and　bearings.　Further　the　earthquake　records　of　the　nearest　Wolong　station　is　chosen　to　be　as　the　earthquake　excitation　input　to　conduct　the　seismic　analysis.　The　analysis　shows　that　the　results　of　damage　position　and　damage　degree　of　components　of　the　bridge　calculated　by　elastic-plastic　dynamic　analysis　are　close　to　the　actual　damage　of　Baihua　Viaduct.　The　reinforcement　ratio　of　piers　is　low,　while　there　is　not　any　shear　failure　on　piers.　The　damage　degree　of　elastic　hinge　is　related　with　the　arrangement　of　bearings.　The　girders＇　displacement　is　much　larger　because　there　are　not　any　anti-dropping　devices　on　the　bridge.　Damage　of　the　fifth　segment　of　bridge　may　be　caused　by　plasticity　destroy　of　some　piers.