A　new　measure,　in　which　sliding　supports　are　used　between　the　staircases　and　the　main　structure,　is　proposed　in　the　current　code　for　seismic　design　of　buildings.　To　experimentally　verify　the　new　measure,　the　shaking　table　test　of　a　large　scaled　structural　unit　of　concrete　frame-staircase　with　sliding　supports　made　of　ploytetrafluoroethene　(PTFE)　plate　was　conducted　to　dynamically　test　its　performance　under　input　motions　of　different　intensities.　It　shows　that,　with　the　sliding　supports　at　the　lower　end　of　the　stairway　slabs,　the　seismic　behavior　of　the　structural　unit　of　concrete　frame-staircase　is　satisfactory;　even　subjected　to　very　severe　motions,　serious　damages　happen　mainly　in　the　members　of　concrete　frame　and　no　serious　failure　occurs　earlier　than　the　frame　in　the　staircase　parts,　including　stairway　slabs,　platform,　supporting　beams　and　columns;　the　sliding　support　made　of　PTFE　plate　works　effectively　and,　horizontally　along　the　direction　of　the　input　motions,　the　lower　ends　of　the　stairway　slabs　can　slide　back　and　forth　as　expected;　meanwhile,　they　also　have　repeated　up　and　down　movements　there.