In　order　to　study　the　influence　of　cross-sectional　constructions　on　seismic　behavior　of　special-shaped　CFT　columns　with　multiple　cavities　in　the　long　axis　direction,　five　specimens　were　tested　under　the　axial　compression　and　twice　loaded　low-cyclic　horizontal　loads.　There　are　one　basic　construction　and　four　enhanced　constructions　in　the　cross-sectional　constructions.　The　four　enhanced　constructions　include　the　enhancement　of　increasing　the　thickness　of　the　longitudinal　steel　plate　in　the　lower　layer　of　the　lower　column　under　bifurcate　plane　and　the　upper　column,　the　enhancement　of　adding　the　cavities　at　the　lower　layer　under　bifurcate　plane,　and　the　enhancements　of　additionally　installing　steel　angles　or　steel　tubes　in　the　corner　cavities　apart　from　the　enhancement　of　adding　the　cavities.　The　test　results　show　that　most　damages　of　specimens　occur　at　the　location　of　horizontal　steel　plate　of　the　lower　column,　and　appear　to　be　cracking　of　steel　plate　in　heat-affected　zones　at　the　weld　edges　and　tearing　of　steel　plate　due　to　the　propagation　of　the　cracks.　The　location　arrangement　of　welds　shall　be　one　of　the　major　factors　influencing　the　failure　patterns　of　the　specimens.　The　enhancement　effect　of　installing　steel　angles　or　steel　tube　in　the　corner　cavities　shall　be　the　best,　the　next　is　that　of　increasing　the　thickness　of　steel　plate,　while　the　worst　is　that　of　adding　multiple　cavities.　The　degradations　of　bearing　capacity　of　all　the　specimens　are　not　remarkable.　The　deformation　and　energy　dissipation　ability　of　the　upper　column　is　better　than　that　of　lower　column.　The　average　value　of　yield　drift　ratio　of　all　the　specimens　is　1/101,　the　drift　ratio　corresponding　to　the　peak　load　is　about　1/42,　and　the　maximum　elasto-plastic　drift　ratio　is　about　1/29,　indicating　that　the　columns　proposed　in　this　work　can　be　used　in　the　design　of　mega　frame　structures　of　super　high-rise　buildings.　©　2018,　Editorial　Office　of　China　Civil　Engineering　Journal.　All　right　reserved.