Biocompatible　materials　and　biocarriers　have　attracted　great　attention　in　biological　wastewater　treatment　owing　to　their　excellent　performance　in　improving　pollutant　removal.　Graphene-based　material,　a　biocarrier　candidate,　with　excellent　adsorbability　and　conductivity　was　increasingly　applied　in　anaerobic　digestion　due　to　its　exceptional　potential　in　the　adsorption　and　electron　transfer　process.　Nevertheless,　the　green　approach　for　the　formation　of　bio-graphene　complexes　and　their　mechanism　in　dye　removal　is　limited.　The　aim　of　this　study　is　to　investigate　and　assess　the　performance　of　biological　graphene　hydrogel　(BGH)　formed　by　Shewanella　putrefaciens　CN32　on　the　removal　of　methyl　orange　(MO)　and　methylene　blue　(MB).　The　results　showed　that　the　formation　of　BGH　is　determined　by　the　physicochemical　characteristics　of　graphene　oxide,　including　sheet　size,　oxidation　degree,　and　interlayer　distance.　BGHs　significantly　increased　the　removal　efficiency　of　dyes　in　comparison　to　non-graphene　samples,　with　a　24-h　removal　rate　of　MO　and　MB　reaching　92.9%　and　91%,　respectively.　The　synergetic　mechanism　of　BGH　on　the　enhanced　removal　rate　of　organic　dye　can　be　ascribed　to　GO＇s　ability　in　accelerating　extracellular　electron　transfer　and　stimulating　biodegradation　pathways　relating　to　c-type　cytochromes,　including　MtrA　and　MtrC.　These　findings　provided　an　understanding　of　the　relationship　between　graphene-based　nanomaterials　and　Shewanella,　which　facilitated　their　future　application　in　environmental　biotechnology.