Benzyl alcohol was anodically oxidized with and without redox mediators using modified electrodes. The morphologies and characteristics of the modified electrodes with and without redox mediators were analyzed. Cyclic voltammograms; of the modified electrodes showed that the capacitive current and area of the solution-electrode interface were rather large. The CV redox peak with fixed hydroquinone was larger than that without fixed hydroquinone. The yield of benzaldehyde obtained by using the modified anode containing immobilized hydroquinone was better/worse than that obtained with a Pt anode without/with hydroquinone in solution, respectively.