The　excellent　mechanical　and　chemical　characteristics　of　graphene　oxide　(GO)　enable　their　potential　application　in　the　realm　of　membrane　separation.　However,　the　expansion　and　instability　of　GO　nanosheets　in　water　limit　its　application.　In　this　work,　nitrogen-doped　GO　(NGO)　was　obtained　by　a　harmless　hydrothermal　reduction　method.　The　obtained　NGO　films　were　attached　to　a　polyvinylidene　fluoride　support　membrane　by　vacuum　filtration.　By　changing　the　hydrothermal　reaction　temperature,　the　reduction　degree　of　GO　and　doping　amount　of　nitrogen　was　adjusted　to　control　the　inter-layer　structure　and　permeability　of　NGO.　The　defect　of　NGO　nanosheets　and　the　reduction　of　oxygen-containing　functional　groups　could　accelerate　the　transportation　of　water　molecules　through　the　inter-layer　space　of　the　hydrophobic　graphene　sheets.　Significantly,　the　polarization　and　high　adsorption　energy　of　pyridine-N　serve　as　a　supplement　to　the　exclusion　mechanism　of　the　inter-layer　spacing.　NGO　membranes　have　better　permeability　than　the　initial　GO　membranes　without　sacrificing　the　rejection　rate.　The　optimized　NGO　film　has　a　significant　rejection　rate　of　above　99%　for　various　dyes,　such　as　methylene　blue,　Congo　red　and　methyl　blue.