A　series　of　novel　bismuth　oxyhalide　Ag/BiOX　(X=Cl,　Br,　I)　composite　photocatalysts　were　synthesized　by　a　solution-based　photodeposited　method　at　room　temperature.　The　resulting　products　were　characterized　by　powder　X-ray　diffraction　(XRD),　scanning　electron　microscopy　(SEM),　X-ray　photoelectron　spectroscopy　(XPS),　photoluminescence　(PL)　emission　spectroscopy,　UV-Vis　diffuse　reflectance　spectroscopy　(DRS),　and　N　2　physical　adsorption.　The　photocatalytic　activity　of　the　samples　was　evaluated　by　photocatalytic　degradation　of　acid　orange　II　under　visible　light　(420　nm<λ<660　nm)　irradiation.　Analysis　by　N　2　physical　adsorption　showed　that　deposition　of　Ag　decreased　the　specific　surface　area　of　the　catalyst.　UV-Vis　DRS　analysis　indicated　that　the　presence　of　Ag　could　result　in　surface　plasmon　absorption,　effectively　increasing　the　visible　light　absorption　ability　of　BiOCl　and　BiOBr.　Furthermore,　PL　analysis　indicated　that　Ag　could　effectively　suppress　the　recombination　of　photogenerated　electron　(e-)-hole　(h　+)　pairs　of　Ag/BiOX.　Activity　testing　indicated　that　the　deposition　of　an　optimal　amount　of　1%-2%　(w,　mass　fraction)　Ag　brought　about　10,　13,　and　2　fold　increases　in　the　photocatalytic　activity　of　BiOCl,　BiOBr,　and　BiOI,　respectively.　The　high　photocatalytic　performance　of　the　composite　photocatalysts　could　be　attributed　to　the　strong　visible　light　absorption,　silver　plasmon　photocatalysis　role　and　the　recombination　restraint　of　the　e-/h+　pairs　resulting　from　the　presence　of　metal　silver　particles.　©　Editorial　office　of　Acta　Physico-Chimica　Sinica.