The mate (Ilex paraguariensis), a native species from South America, is consumed mainly as beverage, either in a hot (chimarrão) as in cold (tererê) infusion. An important concern is its fungal contamination responsible to affect the physical and nutritional qualities. The radiation processing is effective to reduce the microbiological contamination. The aim of this study was to evaluate the effect of gamma radiation from 60 Co at doses of 0, 3, 5, 7, and 10 kGy in fungal contamination as well as in the nutritional and sensorial characteristics of Ilex paraguariensis as chimarrão and tererê beverage. The results show that the dose of 7 kGy decreases the fungal contamination to a safety levels, however decrease the antioxidant activity in chimarrão and promote a change in color characteristic in both beverages. Besides these effects, the dose of 7 kGy is still indicated once the antioxidant activity loss was minimal although the sensorial attributes changed were not percept by consumers.