A　two-dimensional　(2D)　SnNb2O6　nanosheet-graphene　(SnNb2O6-GR)　nanocomposite　featuring　a　typical　2D-2D　structure　has　been　synthesized　via　a　simple　surface　charge　modified　self-assembly　approach.　The　method　is　afforded　by　electrostatic　attractive　interaction　between　negatively　charged　SnNb2O6　nanosheets　and　modified　graphene　nanosheets　with　a　positively　charged　surface　in　an　aqueous　solution.　The　SnNb2O6-GR　nanocomposite　exhibits　a　distinctly　enhanced　visible　light　photocatalytic　performance　toward　degradation　of　organic　dye　in　water　as　compared　to　blank　SnNb2O6　nanosheets.　The　enhanced　photoactivity　is　attributed　to　the　integrated　factors　of　the　intimate　interfacial　contact　and　unique　2D-2D　morphology　associated　with　SnNbO6　and　GR,　which　are　beneficial　for　harnessing　the　electron　conductivity　of　GR,　facilitating　the　transfer　and　separation　of　photogenerated　charge　carriers　over　SnNbO6-GR　upon　visible　light　irradiation,　and　thereby　contributing　to　the　photoactivity　enhancement.　It　is　hoped　that　this　work　could　enrich　the　facile,　efficient　fabrication　of　various　2D-2D　semiconductor　nanosheet-graphene　composite　photocatalysts　toward　target　photocatalytic　applications.　©　The　Royal　Society　of　Chemistry　2014.