Pheolic compounds, including phenol and DCP (2,4-Dichlorophenol), are one of the most toxic compounds commonly found in chemical, pharmaceutical, textile, and petrochemical industrial wastes. This compound has been considered a great potential risk for the environment and human health. Previous studies have shown that it can be removed from industrial wastes by several biological and physical-chemical methods such as chemical adsorption and oxidation techniques, however, these methods are still considered to possess distinctive disadvantages. This is the first study to employ the use of a prototype of cold plasma Dielectric Barrier Discharge (DBD) reactor, with a coaxial configuration. The purpose of this study was to investigate the degradation process of phenolic compounds, obtained from synthetic wastewater into a simpler compound. The performance of the DBD plasma reactor and the effects of various parameters, such as air flow rates 2 - 2.5 L/min and water flow rates 50 - 100 mL/min, combination with ozonation, and the presence of iron in treated wastewater have been investigated. The results showed the DBD plasma reactor was successfully removed phenol as a water pollutant, achieving 98% efficiency with a combination of ozonation.