The effect of the current intensity in the electrochemical oxidation of aqueous phenol wastes at an activated carbon and steel anode was investigated. Results confirm that three reaction pathways were involved in the electrochemical process: direct degradation or electrochemical cold combustion, chemical oxidation, and polymerization. The chemical oxidation pathway was the most important for the range of current intensities studied. To interpret the experimental behavior, a simple mathematical model was proposed and tested, obtaining good agreements between experimental and simulated data.