Bismuth　oxybromide/oxyiodide　(Bi　4　O　5　Br　x　I　2-x　)　photocatalysts　were　successfully　fabricated　using　a　facile　homogeneous　precipitation　method　at　room　temperature.　The　obtained　Bi　4　O　5　Br　x　I　2-x　demonstrated　highly　enhanced　visible-light　performances　compared　with　Bi　4　O　5　Br　2　and　Bi　4　O　5　I　2　.　The　poducts　were　characterized　by　X-ray　diffraction　(XRD),　UV–vis　diffuse　reflectance　spectra　(DRS),　X-ray　photoelectron　spectroscopy　(XPS),　scanning　electron　microscope　(SEM),　and　transmission　electron　microscope　(TEM).　The　DRS　analysis　shows　that　the　band　gap　structures　of　Bi　4　O　5　Br　x　I　2-x　have　been　gradually　modulated　by　changing　the　Br/I　molar　ratio.　The　obtained　Bi　4　O　5　Br　x　I　2-x　samples　have　exhibited　efficient　photocatalytic　activities　in　decomposing　resorcinol,　o-phenylphenol,　and　4-tert-butylphenol.　The　Br/I　molar　ratio　has　great　influence　on　the　activity　of　the　photocatalysts,　and　Bi　4　O　5　Br　0.6　I　1.4　exhibited　the　best　activity　which　was　about　2.77　and　1.80　times　higher　than　that　of　Bi　4　O　5　Br　2　and　Bi　4　O　5　I　2　,　respectively.　The　degradation　intermediates　were　identified　by　liquid　chromatography-mass　spectrometry　(LC–MS),　and　the　possible　degradation　pathway　of　resorcinol　over　Bi　4　O　5　Br　x　I　2-x　photocatalysts　was　proposed.　The　strong　visible　light　absorption,　high　charge　separation　efficiency,　and　proper　band　potentials　should　be　responsible　for　the　excellent　activity　of　Bi　4　O　5　Br　x　I　2-x　photocatalyst.　Trapping　experiments　using　radical　scavengers　confirmed　the　generation　of　[rad]O　2　−　,　[rad]OH,　and　h　+　,　but　only　[rad]O　2　−　and　h　+　have　played　the　chief　role　in　removing　organic　pollutants　from　water.　©　2018