This　study　aims　to　establish　a　probabilistic　capacity　model　of　a　wall　pier　under　various　damage　states,　and　the　seismic　vulnerability　of　a　typical　wall　pier　bridge　is　studied.　The　finite　element　analysis　of　the　wall　pier　is　carried　out　by　using　the　layered　shell　element,　and　its　accuracy　is　verified　through　the　comparison　with　the　experimental　results.　A　series　of　wall　pier　samples　are　generated　based　on　the　survey　data,　and　the　corresponding　finite　element　models　are　established.　The　hysteresis　analysis　is　implemented　to　obtain　the　displacement　drift　ratio　of　each　seismic　performance　point.　A　candidate　capacity　model　with　various　factors　is　proposed,　and　the　unknown　parameters　are　estimated　and　filtered　by　the　Bayesian　method.　One　hundred　and　twenty　bridge　samples　of　a　benchmark　bridge　are　generated　by　considering　the　uncertainty　of　parameters,　and　the　finite　element　models　are　established.　The　bridge　samples　and　ground　motions　were　matched　by　one-to-one　correspondence　for　the　nonlinear　time　history　analysis,　and　seismic　vulnerability　models　of　bridge　components　and　system　are　obtained.　The　results　showed　that　the　in-plane　capacity　of　wall　piers　is　mainly　affected　by　axial　compression　ratio,　shear　span　ratio,　and　vertical　reinforcement　ratio.　The　wall　pier　shows　excellent　behavior　in　the　earthquakes.　The　capacity　models　of　wall　piers　can　be　used　for　evaluating　the　damage　states　of　wall　piers,　and　obtaining　the　seismic　vulnerability　model　of　wall　piers　bridges　to　be　used　for　future　seismic　risk　assessment　and　retrofit　prioritization.