Recently, plans to reuse wastewater from wastewater treatment plants have been actively pursued to conserve water resources efficiently. Ozone has strong oxidizing power and is widely used in advanced water treatment process. The purpose of this research is to control the contact time with the amount of ozone to be injected and utilize the process combining the ozone generator and the fine bubble generator to grasp the processing characteristics for optimum color removal rate is there. Experiment results It was found that the ozone supplied to the reactor was completely dissolved in the state of fine bubbles and the supplied ozone amount was almost completely consumed in the initial stage of the reaction. In the case of the color removal rate according to the contact time (2 minutes to 10 minutes), the color removal rate also increases as the contact time elapses, indicating 15.4%, 45.1%, 61.5%, 83.6%, 95.5%. It showed a trend. In addition, it was found that the oxidation of the chromogenic substance by the ozone discharge tube at 10 minutes of operation advanced faster and better, and the color removal rate was continuously removed up to 95.5%. As a result, it was found that the color removal rate increases as logarithmic function increases as the ozone injection amount increases.