Novel　noble　metal　(Rh,　Pd,　Pt)/BiOX(Cl,　Br,　I)　composite　photocatalysts　were　prepared　and　well　characterized　by　nitrogen-physical　adsorption,　powder　X-ray　diffraction　(XRD),　scanning　electron　microscopy　(SEM),　transmission　electron　microscopy　(TEM),　UV-vis　diffuse　reflectance　spectra　(DRS),　X-ray　photoelectron　spectroscopy　(XPS),　and　photoluminescence　(PL)　emission　spectroscopy.　The　effects　of　noble　metals　deposition　on　the　optical　and　photocatalytic　performance　of　BiOX　in　degradation　of　the　acid　orange　II　dye　under　both　UV　and　visible　light　irradiation　were　systematically　investigated.　Results　show　that　noble　metal　depositions　enhance　their　visible　light　absorption　and　photocatalytic　performance.　However,　catalytic　activity　is　controlled　by　the　species　and　concentration　of　noble　metal.　Over　BiOCl,　the　noble　metals,　abilities　to　promote　activity　are　in　the　orders　Pt　＞　Pd　＞　Rh　and　Rh　＞　Pt　＞　Pd　under　UV　light　and　visible　light　irradiation,　respectively.　Over　different　BiOX　with　optimal　noble　metal　content,　the　best　UV　light　activities　are　in　the　order　Pd(0.5%)/BiOBr　＞　Pt(1%)/BiOCl　＞　Pd(2%)/BiOCl.　Under　visible　light　illumination,　the　best　activities　change　to　Pd(4%)/BiOBr　＞　Pd(0.5%)/BiOI　＞　Rh(1%)/BiOCl.　The　enhanced　photocatalytic　efficiency　could　be　attributed　to　the　promoted　separation　rate　of　photo-generated　e(-)/h(+)　pairs　and　the　role　of　plasmon　photocatalysis　caused　by　deposited　noble　metal　nanoparticles.　(C)　2013　Elsevier　B.V.　All　rights　reserved.