In　past　years,　the　presence　of　toxic　heavy　metal　ions　in　water　and　soil　has　caused　major　health　problems.　The　ternary　type　semiconductor　material,　reduced　graphene　oxide　(rGO)-Sm2MoO6-TiO2,　has　been　investigated　as　a　photocatalyst　for　the　reduction　of　soluble　chromium(VI)　into　(III)　for　the　first　time.　The　as-synthesized　rGO-Sm2MoO6-TiO2　catalyst　was　analyzed　by　X-ray　diffraction　(XRD),　scanning　electron　microscopy　(SEM),　transmission　electron　microscopy,　X-ray　photoelectron　spectroscopy,　FT-Raman,　Fourier　transform　infrared,　and　optical　spectroscopy.　The　maximum　Cr(VI)　reduction　of　96%　was　achieved　within　70　min　under　visible　light　illumination.　The　powder　XRD　analysis　confirmed　the　formation　of　anatase　TiO2.　Field-emission　SEM　images　depicted　well-dispersed　rGO　sheets,　and　TiO2　and　Sm2MoO6　particles　are　randomly　distributed　onto　rGO.　The　reduction　of　Cr(VI)　by　rGO-Sm2MoO6-TiO2　was　considerably　greater　than　the　reduction　by　Sm2MoO6,　TiO2,　Sm2MoO6-rGO,　TiO2-rGO,　and　Sm2MoO6-TiO2.　Sm2MoO6　acts　as　an　effective　cocatalyst　to　TiO2　to　enhance　the　separation　of　photo-generated　electron-holes.　Even　after　six　consecutive　cycles,　the　photoreduction　of　Cr(VI)　was　more　than　85%,　which　reveals　that　the　excellent　reusability　performance　of　the　catalyst　for　practical　applications.　The　photogenerated　electron　plays　an　important　role　in　the　reduction　of　Cr(VI)　into　nontoxic　Cr(III),　and　the　synergistic　effect　of　rGO　greatly　improved　the　separation　of　h(+)　and　e(-)　pairs.