Ultra-High　Performance　Concrete　Filled　Stainless　Steel　Tubular　(UHPCFSST)　column　is　a　novel　type　of　composite　columns　appealing　to　be　adopted　in　corrosive　and　marine　environment.　To　explore　the　axial　performance　of　UHPCFSST　columns,　this　paper　initiates　an　experimental　program　containing　14　UHPCFSST　columns　subjected　to　either　monotonic　or　cyclical　axial　compressive　loading.　The　test　variables　in　this　program　mainly　include　the　column　dimension,　tube　thickness　and　the　loading　schemes.　Based　on　the　test　results,　the　damage　evolution　process,　ultimate　failure　mode,　load-deformation　response　and　the　typical　mechanical　performance　indexes　inclusive　of　loading-carrying　capacity,　stiffness　degradation,　as　well　as　ductility　coefficient　are　thoroughly　examined.　After　that,　theoretical　analysis　is　carried　out　to　explore　the　interaction　behavior　between　UHPC　and　stainless-steel　tube　and　hence　judge　the　degree　of　confinement　effect.　To　assess　the　applicability　of　the　code　equations　stipulated　in　current　international　design　guidelines　and　the　empirical　formulas　proposed　by　other　researchers,　a　small-scale　dataset　containing　41　UHPCFSST　columns　was　compiled　to　make　comparison　of　axial　capacity　between　test　results　and　analytical　predictions.　In　view　of　the　limited　accuracy　or　the　burdensome　calculation　process,　a　new　formula　considering　actual　loading　carrying　mechanism　was　proposed　to　calculate　the　axial　capacity　of　UHPCFSST　columns,　which　exhibits　enhanced　accuracy　and　efficiency　than　the　current　formulas.