Round-ended　concrete-filled　steel　tubular　(CFST)　columns　have　numerous　benefits,　including　easy　construction,　aesthetic　appearance,　and　variable　section　arrangement.　This　study　experimentally　and　numerically　investigated　the　flexural　behavior　of　round-ended　CFST　columns.　The　six　testing　results　showed　that　as　the　aspect　ratio　increased　from　1.38　to　1.86,　the　flexural　resistance　and　stiffness　increased　by　82.0%　and　159.9%,　respectively.　Every　round-ended　CFST　specimen　had　excellent　ductility.　Concrete　can　be　adequately　confined　by　the　round-ended　steel　tube.　Mechanistic　and　parametric　analyses　were　carried　out　using　a　finite　element　model.　Mechanistic　analysis　demonstrated　that　the　round　segment　of　the　steel　tube　can　effectively　confine　the　concrete,　resulting　in　a　considerable　strength　gain　near　the　edge　of　the　compression　zone.　The　parametric　analyses　showed　that　as　the　concrete　strength　increased　from　24　to　110　MPa,　the　flexural　resistance　increased　by　average　20.4%;　as　the　steel　strength　improved　from　235　to　700　MPa,　the　flexural　resistance　increased　by　average　155.4%;　as　the　steel　ratio　enhanced　from　0.05　to　0.2,　the　flexural　resistance　increased　by　average　179.7%;　and　as　the　aspect　ratio　increased　from　1　to　3,　the　flexural　resistance　of　the　major　(minor)　axis　increased　(decreased)　by　about　59.9%　(36.5%).　The　analysis　showed　that　the　flexural　stiffness　of　this　composite　specimen　can　be　accurately　predicted　by　AISC　360–2016.　Finally,　a　simplified　model　was　proposed　for　estimating　the　flexural　resistance　of　the　round-ended　CFST　specimens.　©　2024　Elsevier　Ltd