Ozone generator by using dielectric barrier discharge plasma (DBDP) has been studied. DBDP reactor was constructed with spiral cylender configuration. We found that ozone concentration increased with increasing of voltage, number of spools coil. The ozone concentration decreases with increasing distance between spiral electrode and cylender electrode. We found something very interesting in the generation of ozone, where electrc current has been measured, in other words ionization has occurred, but ozone was not formed. It can be interpreted that although ionization has occurred but oxygen molecular dissociation has not happened or is not enough for the formation of ozone.