In　this　paper,　the　effect　of　organic　sulfur　on　the　catalytic　oxidation　of　toluene　was　explored.　It　was　found　that　the　low　concentration　of　organic　sulfur　could　cause　rapid　deactivation　of　the　catalyst,　and　the　activity　of　the　catalyst　could　be　restored　to　100%　after　stopping　the　application　of　sulfur.　The　sulfation　modification　could　significantly　improve　the　organic　sulfur　resistance　of　the　catalyst　by　changing　the　support　and　the　sulfation　modification　of　the　support.　There　was　a　large　amount　of　carbon　deposition　and　a　small　amount　of　S-containing　substances　on　the　catalyst　surface　after　the　introduction　of　organic　sulfur　through　the　methods　of　TG,　BET,　FTIR,　SEM　(Mapping)　and　XPS.　Then,　through　in-situ　DRIFT　and　CH3SH-TPD,　it　was　found　that　sulfation　modification　could　inhibit　the　adsorption　of　organic　sulfur　on　the　catalyst　surface　and　reduce　the　competitive　adsorption.　The　decrease　of　catalyst　efficiency　due　to　the　presence　of　organic　sulfur　in　the　reaction　gas　during　VOCs　catalytic　oxidation　is　mainly　due　to　the　competitive　adsorption　of　organic　sulfur　and　VOCs　molecules,　and　the　temperature　of　VOCs　catalytic　oxidation　of　organic　sulfur.　Some　polyhydrocarbons,　ethyl　sulfide,　dimethyl　sulfoxide　and　other　substances　were　produced　by　incomplete　oxidation,　which　covered　the　surface　of　the　catalyst　due　to　adsorption　or　deposition,　resulting　in　catalyst　poisoning.