The comparative study on the electro-generation of H2O2 using an activated carbon fiber cathode and graphite cathode was investigated. The effect of the operating parameters on the H2O2 generation concentration and current efficiency, such as the initial pH, current density and electrolyte concentration, was also evaluated. The results revealed that the activated carbon fiber cathode was more effective compared to the graphite cathode. The maximum value of H2O2 concentration could be achieved with pH 3.00, current density 8.89 mA/cm2 and electrolyte concentration 0.05 mol/L. However, due to the formation of competitive electrode reactions, the current efficiency of this electrolysis system is lower than other electrolysis system. In addition, a new kinetic model was established to well describe the electro-generation of H2O2. The experimental data were fitted well using the kinetic model.