High　efficient　numerical　models　that　can　simulate　the　behaviors　of　an　entire　structural　system　are　very　important　to　the　study　on　the　fire-induced　progressive　collapse　of　RC　frame　structures.　A　fire-induced　collapse　simulation　program　is　developed,　which　is　based　on　the　fiber　beam　model　and　the　multi-layer　shell　model.　The　constitutive　models　of　materials　at　high　temperature　are　discussed.　And　the　accuracy　of　the　program　in　simulating　RC　members　in　fire　is　verified　by　test　results.　At　last,　the　progressive　collapse　of　an　8-storey　frame　in　fire　is　simulated　and　the　mechanism　of　collapse　is　discussed.