The decomposition of dimethyl sulfide (DMS) at initial concentrations of 4.5-18.0 ppmv in air was studied under electron-beam (EB) irradiation. Doses to decompose 90% of input DMS were 2.5 kGy for 4.5 ppmv, 3.4 kGy for 10.6 ppmv, and 3.9 kGy for 18.0 ppmv. HCOOH, (CH3)(2)SO, and trace CH3OH and (CH3)(2)SO2 were produced as irradiation products in addition to CO2 and CO. Application of an O-3 decomposition catalyst to an irradiated sample gas led to an enhancement in the oxidation of DMS and its products into CO2 and the decomposition of O-3. For 10.6 ppmv DMS/air, the mineralization ratio increased from 41% via only EB irradiation to 100% via the combination treatment at 6.3 kGy. The yield of CO2 to COx increased from 5.3 to 87.6% by combination with catalytic oxidation. This combination treatment enables the irradiation energy used to deodorize gas streams containing DMS to be reduced.