In　this　study,　high-strength　cables　were　used　to　create　a　prestressed　T-type　self-centering　energy-dissipation　brace　(PTSEB),　which　can　be　used　for　multi-story　and　high-rise　frame　structures.　The　brace　can　dissipate　energy　through　friction,　provide　lateral　stiffness　through　prestressed　cables,　and　automatically　return　to　its　original　position　under　the　action　of　cable　tension　after　the　external　load　disappears.　Lever　action　is　used　to　significantly　amplify　the　deformation　ability　of　the　brace.　Moreover,　the　energy-dissipation　ability　of　the　brace　is　considerably　better　than　that　of　a　traditional　self-centering　brace.　A　test　and　a　finite　element　analysis　were　performed　on　the　PTSEB,　and　the　results　indicated　that　the　brace　had　a　strong　energy-dissipation　ability,　as　well　as　a　high　deformation　capacity　and　self-centering　capacity.　ABAQUS　was　used　to　analyze　and　compare　the　performance　of　braces　with　different　sizes.　The　results　showed　that　in　a　certain　range,　as　the　shell　height　increased,　the　seismic　performance　of　the　PTSEB　was　improved　significantly;　however,　an　increase　in　the　shell　width　did　not　improve　the　seismic　performance　of　the　PTSEB　significantly.　Reasonable　sizes　for　the　PTSEB　were　proposed　based　on　a　finite　element　parameter　analysis　to　ensure　that　the　brace　would　have　improved　energy-dissipation　and　self　centering　abilities.　A　restoring　force　model　of　the　PTSEB　was　constructed,　and　the　key　points　of　the　restoring　force　model　were　obtained　using　some　proposed　formulas.　The　design　parameters　of　the　PTSEB　could　be　determined　based　on　these　formulas.