2-(6-oxido-6Hdiben-(c,　e)(1,　2)-oxaphosphorin-6-yl)-1,　4-bis(5＇,　5＇-dimethyl-1,　4-dioxaphosphorinanyl-2-oxy)　benzene　(DPPOBQ),　a　novel　halogen-free　flame　retardant　with　phosphaphenanthrene　group,　was　synthesized　via　phospous　oxychloride,　neopentyl　glycol,　9,　10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide　(DOPO)　and　1,　4-benzoquinone　by　a　three　step　reaction.　And　the　structure　of　DPPOBQ　was　characterized　and　studied　by　mass　spectrometry　(MS),　elementary　analysis,　fourier　transform　infrared　spectra　(FT-IR),　1H　and　31P　nuclear　magnetic　resonance　spectrum　(1H-NMR,　31P-NMR),　respectively.　Then　the　flame　retardance　in　EVA　foam　composites　was　discussed.　The　results　of　TG-Mass　show　that　the　flame　retardant　has　a　high　thermal　stability　and　excellent　char-forming　ability.　The　5%　weight　loss　temperature　of　title　compound　was　above　260.2℃　and　the　char　yield　was　about　19.1%　at　1000℃.　©,　2015,　Journal　of　Functional　Materials.　All　right　reserved.