Using trimethylopropane trimethylacrylate (TMPTMA) as crosslinking sensitizer, ethylene propylene dine terpolymer rubber (EPDM) was vulcanized by 60Co irradiation method. It has been found that the gel fraction of EPDM increases with the TMPTMA dosage and the appropriate dosage is 8% in weight percentage to EPDM. Tensile strength increases with the absorbed dose until 120 kGy. And the adopted absorbed dose is about 80 kGy. At the same time, the properties of aging resistance and thermal stability of radiation vulcanizate are improved compared with chemical vulcanizate. TG results show that the thermal decomposition temperature of radiation vulcanizate (480℃-530℃) is higher than that of chemical vulcanizate (430℃-480℃). These experimental results indicate that the properties of aging resistance and thermal stability of radiation vulcanizate are better than those of chemical vulcanizate.Cited