The　formation　of　nitrogen-doped　(N-doped)　graphene　uses　hydrothermal　method　with　urea　as　reducing　agent　and　nitrogen　source.　The　surface　elemental　composition　of　the　catalyst　was　analyzed　through　XPS,　which　showed　a　high　content　of　a　total　N　species　(7.12　at.%),　indicative　of　the　effective　N-doping,　present　in　the　form　of　pyridinic　N,　pyrrolic　N　and　graphitic　N　groups.　Moreover,　Au　nanoparticles　deposited　on　ZnO　nanocrystals　surface,　forming　Au/ZnO　hybrid　nanocatalysts,　undergo　a　super-hydrophobic　to　super-hydrophilic　conversion.　Herein,　we　present　Au/ZnO　hybrid　nanocatalysts　impregnated　in　N-doped　graphene　sheets　through　sonication　technique　of　the　Au/ZnO/N-doped　graphene　hybrid　nanostructures.　The　as-prepared　Au/ZnO/N-doped　graphene　hybrid　nanostructure　modified　glassy　carbon　electrode　(Au/ZnO/N-doped　graphene/GCE)　was　first　employed　for　the　simultaneous　determination　of　ascorbic　acid　(AA),　dopamine　(DA)　and　acetaminophen　(AC).　The　oxidation　over-potentials　of　AA,　DA　and　AC　decreased　dramatically,　and　their　oxidation　peak　currents　increased　significantly　at　Au/ZnO/N-doped　graphene/GCE　compared　to　those　obtained　at　the　N-doped　graphene/GCE　and　bare　CCE.　The　peak　separations　between　AA　and　DA,　DA　and　AC,　and　AC　and　AA　are　large　up　to　195,　198　and　393　my,　respectively.　The　calibration　curves　for　AA,　DA　and　AC　were　obtained　in　the　range　of　30.00-13.00　x　10(3),　2.00-0.18　x　10(3)　and　5.00-3.10　x　10(3)　mu　M,　respectively.　The　detection　limits　(S/N　=　3)　were　5.00,　0.40　and　0.80　mu　M　for　AA,　DA　and　AC,　respectively.　(C)　2016　Elsevier　B.V.　All　rights　reserved.