As-prepared epoxy resin samples were surface fluorinated using a F 2 /N 2 mixture. The fluorination resulted in a remarkable increase in surface conductivity of the epoxy sample by over three orders of magnitude. Corona charges deposited on the fluorinated surface could not be stored even at room temperature. Obvious dependence of surface conductivity and steady state surface current on ambient humidity was found for the fluorinated sample. ATR-IR analysis and SEM imaging of surface and cross-section demonstrated substantial changes in surface layer chemical composition and morphology due to the fluorination, which are responsible for the changes in surface electrical properties.