Incorporating　outstanding　flame　retardancy　and　electromagnetic　interference　shielding　effectiveness　(EMI　SE)　into　polymers　is　a　pressing　requirement　for　practical　utilization.　In　this　study,　we　first　employed　the　principles　of　microencapsulation　and　electrostatic　interaction-driven　self-assembly　to　encapsulate　polyethyleneimine　(PEI)　molecules　and　Ti3C2Tx　nanosheets　on　the　surface　of　ammonium　polyphosphate　(APP),　forming　a　double-layer-encapsulated　structure　of　ammonium　polyphosphate　(APP@PEI@Ti3C2Tx).　Subsequently,　flame-retardant　thermoplastic　polyurethane　(TPU)　composites　were　fabricated　by　melting　the　flame-retardant　agent　with　TPU.　Afterwards,　by　using　air-assisted　thermocompression　technology,　we　combined　a　reduced　graphene　oxide　(rGO)　film　with　flame-retardant　TPU　composites　to　fabricate　hierarchical　TPU/APP@PEI@Ti3C2Tx/rGO　composites.　We　systematically　studied　the　combustion　behavior,　flame　retardancy,　and　smoke-suppression　performance　of　these　composite　materials,　as　well　as　the　flame-retardant　mechanism　of　the　expansion　system.　The　results　indicated　a　significant　improvement　in　the　interface　interaction　between　APP@PEI@Ti3C2Tx　and　the　TPU　matrix.　Compared　to　pure　TPU,　the　TPU/10APP@PEI@1TC　composite　exhibited　reductions　of　84.1%,　43.2%,　62.4%,　and　85.2%　in　peak　heat　release　rate,　total　heat　release,　total　smoke　release,　and　total　carbon　dioxide　yield,　respectively.　The　averaged　EMI　SE　of　hierarchical　TPU/5APP@PEI@1TC/rGO　also　reached　15.53　dB　in　the　X-band.　©　2024　by　the　authors.