SO2-4/TiO2　catalysts　were　prepared　by　microwave,　composite　and　conventional　methods　and　characterized　by　X-ray　diffraction　(XRD),　N2　sorption　analysis　applying　BET　method,　UV-Vis　diffuse　reflection　spectroscopy(DRS)　and　laser　Raman　spectrum.　The　effect　of　different　preparation　methods　on　photocatalytic　oxidation　of　C2H4　in　air　stream　was　studied.　The　results　showed　that　the　photocatalytic　activity　was　obviously　increased　by　the　microwave　method.　The　conversion　of　ethylene　was　80%　contrast　to　those　of　composite　and　conventional　methods　being　only　58%　and　41%　,　respectively.　The　catalyst　by　microwave　method　exhibited　higher　content　of　anatase,　higher　specific　surface　area,　larger　band　gap.　The　Raman　scattering　shifted　to　low　wave　number　direction　helped　to　increase　the　transition　probability　of　photon-generated　electrons　and　improved　photoefficiency.