Square　double-skin　concrete-filled　steel　tubular　(DSCFST)　columns　and　concrete-filled　double　steel　(CFDST)　columns　possess　excellent　load-carrying　capacity　and　ductility.　However,　there　has　been　limited　research　on　the　responses　of　DSCFST　and　square　CFDST　columns　exposed　to　fire.　This　paper　presents　a　series　of　tests　on　such　columns　loaded　concentrically　to　determine　the　effects　of　the　steel　tube　thickness,　the　strength　of　materials,　load　ratio,　and　boundary　conditions　on　their　fire　resistance.　Additionally,　finite　element　(FE)　models　are　established　using　ABAQUS,　in　which　the　concrete＇s　transient　creep　strain　is　considered　through　the　development　of　the　usersubroutine　UEXPAN.　A　parametric　study　is　undertaken　by　simulating　156　FE　models　to　further　study　the　behavior　of　DSCFST　and　CFDST　columns　under　fire　exposure.　The　fire　test　and　numerical　results　suggest　that　both　the　load　ratio　and　strengths　of　the　internal　tube　and　concrete　core　play　significant　roles　in　determining　the　fire　resistance　of　DSCFST　and　CFDST　columns.　The　developed　FE　models　are　demonstrated　to　capture　well　the　fire　behavior　of　loaded　DSCFST　and　CFDST　columns.　The　proposed　design　model　predicts　the　ultimate　loads　of　DSCFST　columns　with　good　accuracy;　therefore,　it　can　be　employed　in　the　practical　design　of　DSCFST　columns.