Current-voltage characteristics (CVC) and acetone vapors oxidation in atmospheric pressure corona discharge (CD) of negative and positive polarity were studied in double wires-to-plate geometry. Negative CD was more stable than positive one towards breakdown and allowed to reach higher current. CVC for negative CD can be well described by model for cylindrical geometry with correction in one coefficient only. The ignition voltage of negative CD obeys Peek's law. The rate of acetone vapors oxidation increased with the increase of corona wire radius in the range of discharge power 15-60 W. The highest oxidation rate was obtained at power 60 W, negative polarity and wire radius 400 mu m but the highest energetic efficiency (g/kWh) was obtained at maximum wire radius (400 mu m) and minimum power level (15 W). The oxidation rate was directly proportional to the volume of discharge area which grows together with the increase of wire radius.