Porous　SO2-4/TiO2　solid　superacid　catalysts　with　high　specific　surface　area　were　prepared　by　sol-gel　method　and　characterized　by　X-ray　diffraction　(XRD),　X-ray　photoelectron　spectroscopy　(XPS),　N2　sorption　analysis　applying　BET　method,　and　UV-Vis　reflectance　spectroscopy.　Photocatalytic　oxidation　of　CH3Br,　C6H6　and　C2H4　in　air　stream　was　studied　over　pure　and　sulfated　TiO2　catalysts,　respectively.　The　results　showed　that　the　photocatalytic　and　structural　properties　of　TiO2　were　greatly　improved　by　sulfation.　The　sulfated　TiO2(SO2-4/TiO2)　exhibited　excellent　reaction　activity　for　photocatalytic　decomposition　of　the　organic　compounds.　When　compared　to　unmodified　TiO2,　the　sulfated　TiO2　exhibited　higher　resistance　to　crystal　phase　transformation　from　anatase　to　rutile,　higher　resistance　to　crystal　grain　growth,　higher　specific　surface　area.　As　a　result　of　sulfation,　the　band　gap　of　SO2-4/TiO2　increased　and　the　band　edge　blue-shifted　to　yield　larger　redox　potential,　leading　to　the　increased　photocatalytic　efficiency.