The effects of ozone ultrafine bubble (UFB) formation on ozone concentration and lifetime were experimentally investigated. The results of this study showed that the ozone concentration increased with UFB. It was also shown that the increase in ozone concentration is closely related to the increase in the number of UFBs and specific surface area. Regarding the lifetime of ozone concentration, the half-life of the concentration increased by approximately 1.7 times with UFB conversion. This may be attributed to the fact that ozone-UFB water causes almost no change in mean particle size and particle number over time compared to ozonated water.