In　practice,　fire　is　one　of　the　accidental　loads　that　can　result　in　the　progressive　collapse　of　buildings　but　the　commonly　used　alternate　load　path　(ALP)　approach　often　ignores　the　impact　of　fire.　Therefore,　numerical　models　based　on　the　finite　element　software　ABAQUS　are　employed　to　investigate　the　performance　of　reinforced　con-crete　(RC)　beam-column　assemblies　during　and　after　high　temperature　to　resist　progressive　collapse.　The　ther-mal-mechanical　sequential　coupling　method　is　used　for　analysis.　The　effects　of　fire　durations,　boundary　conditions　(middle　or　penultimate　column　removal)　and　side　column　subject　to　fire　are　studied.　Previous　test　results　demonstrated　that　compressive　arch　action　(CAA)　and　catenary　action　(CA)　are　developed　in　sequence　to　prevent　progressive　collapse　for　the　assemblies　at　ambient　temperature.　However,　the　numerical　results　show　that　the　in-fire　assemblies　could　not　develop　CA　owing　to　severe　degradation　of　rebar　elongation　and　thus,　the　load　resistance　of　in-fire　assemblies　controlled　by　CAA　capacity.　Further　increasing　fire　duration　to　90　mins,　the　CAA　capacity　of　the　assemblies　decreases　over　70%　compared　with　that　at　ambient　temperature.　Since　the　rebar　can　recover　most　of　its　mechanical　properties　after　cooling　down,　the　assembly　after　fire　(i.e.,　exposed　to　fire　then　cooled　down)　can　also　successively　develop　flexural　action　(FA),　compressive　arch　action　(CAA)　and　catenary　action　(CA)　to　resist　progressive　collapse,　which　is　similar　to　that　of　intact　RC　frame　at　ambient　temperature.　Under　the　penultimate　column　removal　scenario,　the　exterior　side　column　of　the　post-fire　specimen　suffers　large　eccentric　compression　failure,　which　causes　the　highest　collapse　risk.