Highly　reductive　RGO　(reduced　graphene　oxide)/ZnIn2S4　nanocomposites　with　a　sheet-on-sheet　morphology　have　been　prepared　via　a　facile　one-pot　solvothermal　method　in　a　mixture　of　N,N-dimethylformamide　(DMF)　and　ethylene　glycol　(EG)　as　solvent.　A　reduction　of　GO　(graphene　oxide)　to　RGO　and　the　formation　of　ZnIn2S4　nanosheets　on　highly　reductive　RGO　has　been　simultaneously　achieved.　The　effect　of　the　solvents　on　the　morphology　of　final　products　has　been　investigated　and　the　formation　mechanism　was　proposed.　The　as-prepared　RGO/ZnIn2S4　nanoscomposites　were　characterized　by　powder　X-ray　diffraction　(XRD),　Fourier　transform　infrared　spectroscopy　(FT-IR),　Raman　spectroscopy,　X-ray　photoelectron　spectroscopy　(XPS),　N2-adsorption　BET　surface　area,　UV-vis　diffuse　reflectance　spectroscopy　(DRS),　scanning　electron　microscopy　(SEM),　transmission　electron　microscopy　(TEM),　high-resolution　transmission　electron　microscopy　(HRTEM).　The　photocatalytic　activity　for　hydrogen　evolution　under　visible　light　irradiations　over　the　as-prepared　RGO/ZnIn2S4　nanocomposites　has　been　investigated.　The　as-prepared　RGO/ZnIn2S4　nanocomposites　show　enhanced　photocatalytic　activity　for　hydrogen　evolution　under　visible　light　irradiations　and　an　optimum　photocatalytic　activity　is　observed　over　1.0　wt　%　RGO　incorporated　ZnIn2S4　nanocomposite.　The　superior　photocatalytic　performance　observed　over　RGO/ZnIn2S4　nanocomposites　can　be　ascribed　to　the　existence　of　highly　reductive　RGO　which　has　strong　interactions　with　ZnIn2S4　nanosheets.　The　existence　of　the　strong　interaction　between　ZnIn2S4　nanosheets　and　RGO　in　the　nancomposites　facilitates　the　electron　transfer　from　ZnIn2S4　to　RGO,　with　the　latter　serving　as　a　good　electron　acceptor,　mediator　as　well　as　the　co-catalyst　for　hydrogen　evolution.　This　study　can　provide　some　guidance　for　us　in　the　developing　of　RGO-incorporated　nanocomposite　photocatalysts.　©　2014　American　Chemical　Society.