To study the effect of oxidative damage of HBE cells induced by radon exposure, HBE cells were exposed to radon (20 000 Bq/m3) with different exposed time (10 min, 20 min and 40 min). The reactive oxygen species (ROS) level, the malondialdehyde (MDA) and the superoxi dismutase (SOD) content in HBE cells was detected respectively. Single cell gel electrophoresis (SCGE) was applied for quantitative analysis of DNA damage in HBE cells induced by radon exposure. Compared with the control group, the level of ROS and the content of MDA increased (p<0.05) significantly, while the content of SOD was decreased (p<0.05) significantly. The SCGE results showed that radon could significantly increase the Olive tail moment in DNA of HBE cells compared with the control group (p<0.05). Exposure to radon could increase the oxidative damage of HBE cells.Cited