The　modified　graphene　oxide(DD-GO)　was　reacted　by　the　Didodecyldimethylammonium　bromide　(DDAB)　and　graphene　oxide,and　then　reduced　via　L-ascorbic　acid　to　obtain　functional　graphene(DD-RGO).　Functional　graphene　(DD-RGO)/thermoplastic　polyurethane　(TPU)　composite　films　were　prepared　by　solution　on　the　coating　machine.　The　morphology　and　properties　of　DD-RGO/TPU　composite　films　were　investigated　by　FTIR,　XRD,　FE-SEM,　oxygen　transmission　rate　tester　and　high　resistance　meter.　The　results　show　that　DD-RGO　with　fold　layer　structure　is　evenly　dispersed　in　TPU　matrix,　and　the　thermal　stability,　barrier　properties　and　antistatic　properties　of　TPU　composite　film　have　been　significantly　improved.　When　the　mass　fraction　of　DD-RGO　is　2%,　compared　with　the　pure　TPU　film,　the　oxygen　transmission　rate　has　been　reduced　by　50%　and　the　volume　resistivity　has　been　increased　by　7　orders　of　magnitude.　The　barrier　properties　and　antistatic　properties　of　composite　films　have　been　improved　significantly.　©　2016,　Journal　of　Materials　Engineering.　All　right　reserved.