Based　on　the　statistical　analysis　of　concrete　filled　steel　tubular　(CFST)　truss　arch　bridges,　considering　the　main　structure　parameters　on　its　out-of-plane　buckling,　a　virtual　bridge　is　built　and　revised　into　a　standard　one　by　referring　to　two　real　bridges.　The　parameter　analyses　are　conducted　on　this　standard　bridge　by　using　the　elastic　buckling　analysis　method.　The　results　show　that　the　out-of-plane　stability　will　be　improved　with　the　increase　of　the　ratio　of　the　width　to　span　of　the　bridge　and　the　decrease　of　the　distances　of　the　bracings;　the　X-shaped　bracings　have　the　largest　improvement　on　the　out-of-plane　stability,　followed　by　K-shaped　and　straight　bracings;　the　stability　becomes　worse　quickly　with　the　increase　of　the　out-of-plane　slenderness　from　80　to140,　and　then　slowly　from　140　to　220.　Finally,　the　elastic　buckling　analysis　method　by　solving　the　eigenvalue　is　discussed.　Discussion　results　indicates　that　the　load　condition　in　the　calculation　should　be　the　case　causing　the　largest　compression　forces　in　the　arch,　and　this　method　can　not　reflect　initial　geometric　defects　and　the　action　of　the　transverse　forces　on　it.