Introduction:　Tumor　vaccines　that　induce　robust　humoral　and　cellular　immune　responses　have　attracted　tremendous　interest　for　cancer　immunotherapy.　Despite　the　tremendous　potential　of　tumor　vaccines　as　an　effective　approach　for　cancer　treatment　and　prevention,　a　major　challenge　in　achieving　sustained　antitumor　immunity　is　inefficient　antigen　delivery　to　secondary　lymphoid　organs,　even　with　adjuvant　aid.Methods:　Herein,　we　present　antigen/adjuvant　integrated　nanocomplexes　termed　nsGO/PCP/OVA　by　employing　graphene　oxide　nanosheet　(nsGO)　as　antigen　nanocarriers　loaded　with　model　antigen　ovalbumin　(OVA)　and　adjuvant,　Poria　cocos　polysaccharides　(PCP).　We　evaluated　the　efficacy　of　nsGO/PCP/OVA　in　activating　antigen-specific　humoral　as　well　as　cellular　immune　responses　and　consequent　tumor　prevention　and　rejection　in　vivo.Results:　The　optimally　formed　nsGO/PCP/OVA　was　approximately　120-150　nm　in　diameter　with　a　uniform　size　distribution.　Nanoparticles　can　be　effectively　engulfed　by　dendritic　cells　(DCs)　through　receptor-mediated　endocytosis,　induced　the　maturation　of　DCs　and　improved　the　delivery　efficiency　both　in　vitro　and　in　vivo.　The　nsGO/PCP/OVA　nanoparticles　also　induced　a　significant　enhancement　of　OVA　antigen-specific　Th1　and　Th2　immune　responses　in　vivo.　In　addition,　vaccination　with　nsGO/PCP/OVA　not　only　significantly　suppressed　tumor　growth　in　prophylactic　treatments,　but　also　achieved　a　therapeutic　effect　in　inhibiting　the　growth　of　already-established　tumors.Conclusion:　Therefore,　this　potent　nanovaccine　platform　with　nanocarrier　nsGO　and　PCP　as　adjuvants　provides　a　promising　strategy　for　boosting　anti-tumor　immunity　for　cancer　immunotherapy.