Bi2Sn2O7,　synthesized　through　different　hydrothermal　routes　(the　microwave　hydrothermal　method　(MH-BSO)　and　the　traditional　hydrothermal　method　(TH-BSO)),　was　used　for　photocatalytic　removal　of　arsenic　from　aqueous　solution.　The　as-synthesized　Bi2Sn2O7　products　were　characterized　by　X-ray　diffraction　(XRD),　N2　sorption-desorption,　UV-Vis　diffuse　reflectance　spectroscopy　(UV-Vis　DRS),　transmission　electron　microscopy　(TEM),　electron　spin　resonance　(ESR),　X-ray　photoelectron　spectra　(XPS),　and　electrochemistry　technology.　Under　visible　light　irradiation,　the　MH-BSO　sample　exhibited　a　higher　photocatalytic　activity　(up　to　98.7%)　than　that　of　the　TH-BSO　sample　during　the　oxidization　of　arsenite　(AsO3)3-.　The　active　species,　O2　-•　and　hVB　+,　were　identified　as　the　primary　active　species　responsible　for　As(III)　oxidation.　In　addition,　a　possible　mechanism　for　the　photo-oxidation　of　As(III)　over　Bi2Sn2O7　is　proposed.　©　Editorial　office　of　Acta　Physico-Chimica　Sinica.