In　extreme　environments,　the　simultaneous　presence　of　mechanical　impact　and　fire　hazards　poses　significant　challenges　for　single　flexible　polyurethane　foam　(FPUF)　protective　materials.　To　address　these　limitations,　we　developed　an　innovative　multilayer　coating　structure　for　FPUF　using　a　simple　dip-drying　method.　This　structure　comprises　a　polydopamine　(PDA)　base　layer,　an　intermediate　layer　containing　ammonium　polyphosphate　(APP),　carboxymethyl　chitosan　(CMC),　and　halloysite　nanotubes　(HNT),　and　a　top　layer　of　polydimethylsiloxane　(PDMS).　The　multilayer　coating　significantly　enhanced　the　cushioning　and　flame-retardant　properties　of　FPUF.　At　a　coating　loading　of　35　wt.%,　the　FPUF@PDA/A-C-H/PDMS　exhibited　a　compressive　strength　3.52　times　higher　than　pure　FPUF,　with　only　a　10.2　%　decrease　after　100　compression　cycles.　The　composite　effectively　dissipated　95.7　%　of　an　impact　energy　of　1.22　J,　achieving　a　97.1　%　impact　force　dissipation　rate　and　significantly　extending　cushioning　duration.　The　FPUF@PDA/A-C-H/PDMS　demonstrated　self-extinguishing　properties　after　10　s　of　exposure　to　a　butane　flame,　maintaining　structural　integrity.　Moreover,　its　peak　heat　release　rate　was　reduced　by　68.8　%.　The　multilayer　coating　also　improved　hydrophobicity　and　thermal　insulation.　This　multifunctional　foam　composite　shows　great　potential　for　enhancing　the　performances　of　FPUF　in　hazardous　environments,　offering　robust　protection　in　extreme　conditions.　©　2025　Elsevier　Ltd