For　exploring　the　essential　mechanical　behaviors　of　concrete　filled　steel　tube　structures　with　high　strength　materials,　nine　circular　ultra-high　performance　concrete　(UHPC)　filled　high-strength　steel　tube　(HS-HC)　short　columns　with　different　steel　ratios　were　tested　to　investigate　their　axial　compressive　behavior.　Additionally,　the　effect　of　steel　strength　and　concrete　strength　on　the　axial　compressive　behavior　were　studied.　Compared　with　the　UHPC　filled　normal-strength　steel　tube　column　and　normal　concrete　filled　high-strength　steel　tube　column,　under　the　same　conditions,　the　local　buckling　of　high-strength　steel　and　the　brittle　of　UHPC　can　be　improved　more　obviously　in　the　UHPC　filled　high-strength　steel　tube　column.　For　avoiding　strength　loss　caused　by　the　more　significant　transverse　expansion　of　the　UHPC,　the　hoop　action　should　be　established　as　soon　as　possible　after　the　yield　of　steel.　This　paper　conducted　parametric　analyses　using　benchmarked　finite　element　models.　The　results　from　parametric　analyses　indicated　that　the　bearing　capacity　of　composite　columns　increases　with　increasing　steel　ratio.　The　influence　of　steel　ratio　on　the　bearing　capacity　is　related　to　steel　strength　rather　than　concrete　strength.　Due　to　the　limitation　of　material　strength,　GB　50936-2014　＇Code　for　concrete-filled　steel　tubular　structures＇　poorly　predicted　the　axial　compressive　strength　of　composite　columns　with　high-strength　materials.　Therefore,　based　on　the　finite　element　data,　a　new　equation　was　proposed　for　estimating　their　bearing　capacity.　The　proposed　equation　with　a　reasonable　accuracy　was　verified　by　experimental　results　obtained　from　this　paper　and　related　literatures,　and　it　can　be　used　in　engineering　applications　of　composite　columns　with　high-strength　materials.　©　2020,　Editorial　Office　of　Journal　of　Building　Structures.　All　right　reserved.