Trinuclear　Fe(III)　acetate　complex　intercalated　montmorillonite　Fenton　catalysts　were　successfully　prepared　by　a　facile　ion　exchange　process.　The　obtained　catalysts　were　characterized　by　X-ray　diffraction,　scanning　electron　microscopy,　transmission　electron　microscopy,　Ultraviolet-visible　(UV-Vis)　diffuse　reflectance　spectroscopy,　X-ray　absorption　fine　structure,　and　inductively　coupled　plasma-atomic　emission　spectrometry.　The　results　showed　that　the　montmorillonite＇s　surface　area　was　greatly　increased　after　the　trinuclear　iron　cluster　intercalated.　A　few　amorphous　nano-fibre　iron　oxides　were　anchored　on　the　surface　of　the　catalyst.　The　prepared　catalyst　exhibited　high　efficiencies　for　the　degradation　and　mineralization　of　rhodamine　B　in　the　presence　of　H　2O　2　under　visible　light　irradiation.　Furthermore,　the　main　active　species　in　catalytic　reaction　process　have　been　investigated.　Based　on　the　experimental　results,　a　possible　mechanism　was　discussed　and　proposed.