With　the　increasing　span　of　steel　box-section　arch　bridges,　the　stability　and　ultimate　strength　of　arch　ribs　under　horizontal　loading　become　crucial　for　earthquake　resistance.　This　paper　presents　a　numerical　study　on　the　cyclic　behavior　of　steel　box-section　twin　arch　ribs　under　out-of-plane　horizontal　cyclic　loading　to　assess　the　seismic　performance　of　steel　box-section　twin　arch　ribs.　Seventy-two　finite　element　(FE)　models　of　arch　ribs　were　established　and　validated　based　on　previous　experimental　studies.　An　pseudo　static　elasto-plastic　numerical　analysis　was　conducted　to　investigate　the　influence　of　the　inclination　angle,　rise-span　ratio,　and　width-span　ratio　on　the　cyclic　behavior　of　the　arch　ribs.　The　results　indicate　that　as　the　angle　of　inclination　and　width-span　ratio　increase,　or　as　the　rise-span　ratio　decreases,　the　initial　stiffness　and　ultimate　strength　of　the　arch　ribs　improve.　However,　this　also　leads　to　an　increase　in　internal　forces　within　the　transverse　brace,　resulting　in　local　instability　and　damage.　In　addition,　the　inclination　angle　of　the　arch　rib　and　the　span-to-rise　ratio　may　influence　the　yielding　sequence　of　the　components.　Therefore,　while　increasing　the　angle　of　inclination　of　the　arch　rib　can　enhance　the　transverse　cyclic　behavior　of　the　steel　box-section　twin　arch　ribs,　it　is　important　to　consider　the　potential　adverse　effects　caused　by　the　increased　internal　forces　on　the　transverse　brace.