The　bottom　strengthened　rectangular　steel　tube　reinforced　concrete　(STRC)　column　was　put　forward.　The　bottom　area　of　the　rectangular　column　was　welded　with　steel　plates　to　improve　the　seismic　capacity.　Three　1/5　scaled　column　models　with　different　structural　measures　were　tested　under　horizontal　low　cyclic　loading.　The　prototype　of　the　model　is　a　kind　of　composite　column　of　super　large　platform　structure　in　Pingxifu　metro　station　of　Beijing.　Model　1　is　a　conventional　rectangular　STRC　column;　Model　2　is　a　rectangular　STRC　column　welded　with　steel　plates　at　the　outer　part　of　the　bottom　in　the　vertical　direction　to　loading;　Model　3　is　a　rectangular　STRC　column　welded　with　steel　plates　at　the　outer　surrounding　part　of　the　bottom.　The　load-bearing　capacity,　stiffness　and　its　degradation　process,　ductility,　hysteretic　energy　dissipation　capacity　and　failure　characteristics　of　the　models　were　analyzed.　The　load-bearing　capacity　calculation　formulae　for　normal　section　and　oblique　section　of　bottom　strengthened　rectangular　STRC　column　was　presented,　and　the　results　obtained　from　the　calculation　are　in　good　agreement　with　those　from　the　experiments.　The　study　shows　that　the　load-bearing　capacity,　ductility　and　seismic　energy　dissipation　capacity　of　the　bottom　strengthened　rectangular　STRC　column　are　improved　obviously　compared　to　the　conventional　rectangular　STRC　column.