A　new　type　of　RC　composite　core　walls　with　steel　tube-reinforced　concrete　columns　and　concealed　steel　truss　was　proposed.　In　order　to　know　the　seismic　performance　of　this　composite　core　walls,　two　1/6　prototypal　scale　perforated　RC　core　walls　specimens　were　designed,　one　of　them　was　composite　core　walls　with　steel　tube-reinforced　concrete　columns,　the　other　one　was　composite　core　walls　with　steel　tube-reinforced　concrete　columns　and　concealed　steel　truss,　and　experimental　study　on　seismic　behavior　of　them　under　the　cyclic　loading　was　carried　out.　Based　on　the　experiment,　the　hysteretic　behavior,　load-carrying　capacity,　ductility,　stiffness　attenuation,　energy　dissipation　and　failure　mode　were　contrastively　discussed.　The　test　results　show　that　the　seismic　performance　of　RC　core　walls　with　steel　tube-reinforced　concrete　columns　is　greatly　improved　by　the　concealed　steel　truss.　Finally,　the　mechanical　model　for　calculating　load-carrying　capacity　of　the　new　type　of　RC　composite　core　walls　was　proposed,　and　the　calculating　results　agreed　well　with　the　suitable　test　results.