[en] Twenty-eight male wistar rats were randomly divided into seven groups, i.e. the radon groups (3), the propolis+radon groups (3) and the control (1). The propolis+radon groups were fed intragastrically with propolis 0.2 g/kg, before exposing them, together with the radon groups, to radon and its progeny with the cumulative dose up to 30, 67 and 111 working level month (WLM), respectively. The levels of SOD (superoxide dismutase) and MDA (Malonic dialdehyde) in blood and lung tissue were determined. The SOD level of in blood and lung tissues of the radon groups decreased significantly and the MDA level increased. The MDA level in lung tissue of the 30 WLM propolis+radon group was significantly higher than the 30 WLM radon group. The SOD level in lung tissue of the 67 WLM propolis+radon group was significantly higher, but the MDA level was significantly lower, than the 67 WLM radon group. Both the SOD and MDA levels in blood and lung tissue of the 111 WLM propolis+radon group were significantly higher than the 111 WLM radon group. In conclusion, the inhalation of radon and its progeny can lead to persistent disturbance of the redox state in rats. Propolis show some protective effects on the redox damage under the experimental conditions. (authors)