In　this　paper,　two　1/6　scale　core　walls　including　a　normal　reinforced　concrete　core　wall　and　a　reinforced　concrete　composite　core　wall　with　concealed　steel　truss　were　designed.　The　experimental　study　on　the　torsional　behavior　of　two　core　walls　subjected　to　eccentric　horizontal　Loading　was　carried　out.　The　torsional　capacity,　torsional　stiffness,　torsional　angle　ductility,　torsion-torsional　hysteretic　behavior,　energy　dissipation　and　failure　mechanism　of　the　core　walls　were　discussed.　The　test　results　showed　that　the　torsional　performance　of　core　walls　was　improved　greatly　by　the　concealed　steel　truss.