A hybrid discharge type ozonizer, which is superposed silent and surface discharges, has been designed and manufactured to apply for Nitrogen Oxides(NO) gas removal. The ozonizer consists of three electrodes, and is classified three types of ozonizer by changing applied voltage. Investigation was carried out variance with the flow rate of supplied oxygen gas, discharge power and the sorts of superposed discharge type ozonizer. Moreover, NO(1200[ppm])/$N_2$ gas removal investigation was also conducted to apply for environment improvement field. Two kinds of NO gas removal investigations were conducted. It distinguishes the investigations into NO gas reaction method. According to these studies, maximum removal rate of 100[%] in NO gas was obtained, and 8334[ppm] and 3249[mg/h] of maximum ozone concentration and generation were also obtained respectively.