Reactive　Powder　Concrete　(RPC)　is　a　new　kind　of　building　material　with　high　strength　and　other　good　performance.　The　combination　of　RPC　and　steel　tube　will　compensate　the　brittleness　of　RPC　and　enhance　the　stability　of　steel　tube,　and　the　loading　capacity　of　the　RPC　filled　steel　tube　will　be　improved.　Five　RPC　filled　steel　tube　columns　are　designed　and　tested　to　obtain　the　ultimate　load　bearing　capacity,　the　deformation　and　the　strain　information.　During　the　loading　process,　the　concrete　and　the　steel　tube　of　the　RPC　filled　steel　tube　columns　are　loaded　simultaneously.　The　loading　results　show　that　the　deformation　of　the　RPC　filled　steel　tube　columns　are　mainly　in　elastic　phase　before　the　loading　capacity　is　up　to　the　ultimate　value.　The　test　load　decreases　to　be　80%∼90%　of　the　ultimate　loading　value　and　then　it　changes　to　be　smooth.　The　failure　mode　of　the　RPC　filled　steel　tube　columns　is　ductile.　The　test　loading　capacity　is　compared　with　the　formula　from　the　reference.　The　tested　ultimate　load　bearing　capacity　of　the　steam　cured　RPC　filled　steel　tube　columns　is　higher　than　the　calculated　value.　The　calculated　value　is　safe　for　the　engineering　application.　The　study　is　useful　for　the　research　and　application　of　RPC　filled　steel　tube　column.　©　(2011)　Trans　Tech　Publications.