In　the　field　of　biomemorizers,　the　simultaneous　enhancement　of　resistive　switching　(RS)　performance　and　environmental　robustness,　and　the　understanding　the　RS　mechanism　involving　interfacial　interaction　is　still　challengeable.　Herein,　the　bio-composites　by　encapsulating　graphene　(GR),　graphene　oxide　(GO)　and　reduced　graphene　oxide　(RGO)　into　chitosan　(CS)　have　been　fabricated　as　memory　devices　with　the　structure　of　FTO/biocomposite/Ag.　Among　them,　FTO/GO@CS(12　%)/Ag　biomemorizer　exhibits　the　best　RS　performance　with　high　ON/OFF　ratio　(10　5.92　),　and　it　possesses　good　thermal　(170　degrees　C)　and　irradiation　stabilities　(UV　exposure　for　96　h).　The　RS　mechanism　is　due　to　the　migration　of　oxygen　vacancies　accompanied　by　formation　of　Ag　conducting　filaments　in　the　bio-composite　films.　Therefore,　the　enhanced　resistive　switching　performance　after　encapsulating　into　CS　can　be　explained　as　the　increment　of　defects,　the　higher　current　densities　and　quenched　radicals.　Specially,　for　the　first　time　we　find　the　presence　of　voltage　-induced　packing　mode　changes　in　GO@CS　composite,　which　can　facilitate　the　migration　of　oxygen　vacancies　and　render　its　best　RS　performance.　In　all,　the　more　carboxyl　groups　can　strengthen　the　GO　-CS　interfacial　interactions　through　the　formation　of　stable　hydrogen　bonding　network　and　covalent　bonds,　which　can　enhance　the　stabilities　and　makes　the　composites　be　more　sensitive　to　electrical　stimulus.　The　rules　drawn　in　this　work　will　be　significant　for　the　construction　of　new　biomemorizers　with　good　environmental　robustness.