Steel　tube　reinforced　concrete　(STRC)　is　a　high-performance　structure　hybrid　of　the　outer　reinforced　concrete　(RC)　and　inner　concrete-filled　steel　tube　(CFST).　Two-stage　initial　stresses　were　generated　in　construction　process　of　STRC　structure,　i.e.,　the　first-stage　steel　tube　initial　stress　and　the　second-stage　CFST　initial　stress,　which　may　affect　the　structural　loading.　This　paper　studies　the　influence　mechanism　of　two-stage　initial　stresses　on　the　ultimate　bearing　capacity　of　STRC　column　by　the　test　databases　and　finite　element　(FE)　analysis.　The　FE　model　was　validated　by　73　tests,　and　a　good　agreement　was　achieved　between　the　tested　and　FE　results　on　failure　mode,　load-displacement,　and　the　ultimate　bearing　capacity.　The　FE　analysis　was　carried　out　to　research　the　influences　of　two-stage　initial　stresses　degree　and　CFST　area　ratio.　The　analysis　results　show　that　the　ultimate　bearing　capacity　of　the　STRC　column　decreased　by　12.0　%　with　the　initial　stress　degree　in　steel　tube　of　0.8,　while　increased　by　6.4　%　with　the　initial　stress　degree　in　CFST　of　0.8.　The　main　reason　for　the　reduction　can　be　attributed　to　the　decreasing　contribution　of　RC,　and　the　improvement　to　the　increasing　contribution　of　CFST.　The　influence　of　two-stage　initial　stresses　on　the　ultimate　bearing　capacity　of　STRC　column　is　related　to　the　initial　stress　degree　of　both　the　steel　tube　and　CFST.　The　two-stage　initial　stresses　influence　coefficient　was　established　by　the　test　and　FE　results　to　predict　the　ultimate　bearing　capacity　of　STRC　columns.　©　2025　Institution　of　Structural　Engineers