Electroconductive　polystyrene　(PS)　composites　with　ideal　flame-retardant　properties　are　considered　as　potential　electromagnetic　interference　(EMI)　shielding　materials.　In　this　work,　PS/silicon　wrapped　ammonium　polyphosphate/multi-wall　carbon　nanotubes　(PS/SiAPP/MWCNT)　composites　with　segregated　structure　were　synthesized　via　the　methods　of　balling　mill　and　hot-pressing.　The　obtained　results　revealed　that　the　SiAPP　and　MWCNT　were　successfully　introduced　onto　PS　spheres　and　showed　uniform　distribution　on　the　PS　surface.　The　thermogravimetric　analysis　showed　that　PS/SiAPP/MWCNT　containing　7　wt%　MWCNT　exhibited　excellent　thermal　stability.　Furthermore,　the　results　of　cone　calorimeter　test　indicated　that　the　heat　release　rate　and　total　heat　release　of　the　PS/SiAPP/MWCNT　containing　a　loading　of　7　wt%　MWCNT　were　reduced　by　60.5%　and　33.9%,　respectively.　In　addition,　the　EMI　shielding　performance　could　reach　11　dB.　Above　results　implied　that　the　synergistic　effect　between　the　MWCNT　and　SiAPP　effectively　enhanced　the　flame　retardant　performance　of　the　PS　by　promoting　the　generation　of　dense　and　continuous　char　layer　to　protect　the　PS　from　burning.　The　multiple　reflection　and　adsorption　are　responsible　for　improved　EMI　shielding　effectiveness.　Therefore,　segregated　PS/SiAPP/MWCNT　hybrid　is　an　up-and-coming　candidate　for　satisfactory　EMI　shielding　materials　with　exceptional　fire　retardancy　for　electronic　devices.　©　2021　Elsevier　Inc.