An　unconventional　method　based　on　hot　filament　chemical　vapor　deposition　system　is　used　to　fabricate　MoO3-x/graphene　nanoflake　hybrid　structures　via　surface　growth.　MoO3　precursor　is　firstly　reduced　to　MoO3-x　nanoparticles　mediated　by　N-2　molecules　excited　by　electrons　emission　from　hot　tungsten　filaments.　Graphene　nanoflakes　are　then　grown　on　the　MoO3-x　nanoparticles　in　a　high-flow-rate　CH4　environment　through　the　surface　conversion　of　hydrocarbon　radicals　to　benzene.　The　results　indicate　that　the　MoO3-x　nanoparticles　are　mainly　composed　of　Mo4O11　and　MoO2　phases　and　they　are　covered　by　the　graphene　nanoflakes　formed　via　surface　growth.　This　new　hybrid　structure　emits　the　ultraviolet,　blue,　green,　red　and　infrared　light　and　the　photoluminescence　of　MoO3-x　nanoparticles　is　quenched　by　the　graphene　nanoflakes.　The　generation　of　prevailing　photoluminescence　bands　is　interpreted　by　the　three　mechanisms　including　the　near　band　edge　emission,　the　transition　between　two　bands　and　the　inter-valence　charge　transfer　transition,　which　indicates　that　the　intermediate　band　formed　within　the　bandgap　by　electrons　from　oxygen　vacancies　may　cause　the　emission.　The　observed　photoluminescence　quenching　of　MoO3-x　nanoparticles　originates　from　the　transfer　of　electrons　from　MoO3-x　nanoparticles　to　graphene　nanoflakes　under　electric　field　formed　in　the　MoO3-x/graphene　nanoflake　interface.　These　results　not　only　provide　further　insights　into　the　rich　surface　properties　of　graphene/olybdenum　oxide　hybrid　structures　but　also　contribute　to　the　design　and　synthesis　of　new　materials　and　the　development　of　next-generation　graphene-based　optoelectronic　and　photovoltaic　devices.