This study applied the advanced oxidation process UV/O3 to remove color and organic matter in the printing ink wastewater, case study for the wastewater of Tan Dong Duong Ink Production Factory - Bien Hoa 1 Industrial Zone - Dong Nai after it was treated by coagulation and flocculation. The results of research which based on the laboratorial model showed that the UV/O3 process was able to remove 83.4 percent of color and 54.3 percent of organic matter in the printing ink wastewater at the optimum conditions: pH = 9, correlative ozone - starting rate of 43.2 mgO3/h, handling time of 80 minutes with 254 om UV lamp. After treating by this AOP process, the color of wastewater reached QCVN 4O:2011/BTNMT - A - The National Technical Standards for Industrial Wastewater
COD reached B - this standard. Also, the results showed that anions such as Cl (0.034 mol/L), HCO3- (0.024 mol/L), SO4 (0.014 mol/L) significantly reduced the efficiency of this AOP process. The results of study are highly reliable because the experiments were conducted with two types of wastewaters (artificial wastewater and real wastewater) and got the similar efficiency.