In this paper, comparative studies were carried out on electrochemical and photo oxidation processes to degrade the synthetic effluent containing ethyl benzene. The electrochemical oxidation was carried out in galvanostatic mode with lead oxide as anode and a stainless steel plate as the cathode in the presence of 2 g/L of NaCl has been added as a supporting electrolyte. The electrochemical treatment was optimized by response surface methodology (RSM), which results in 73.42 % was the highest percentage of COD removal, and the optimum conditions were satisfied at current density 1.82 A/dm 2 , time 2 h, flow rate 10 l/h, volume 3.63 L occurs at minimum power consumption 15 kWh/kg COD. It was followed by the photo oxidation process was carried out in the presence of Ultra Violet radiation emitted from Ultra Violet source was investigated. From the study, it was observed that percentage of COD reduction, and Biodegradability Index was found to be the maximum of 98.42 % and 0.712 respectively, the optimized irradiation time was 45 minutes for pretreated effluent has been investigated. This combined method appears to be a promising technology and has potential application for environmental remediation.