In this study, ethylene glycol (EG) and terephthalic acid (TPA) were used to generate hydrogen using copper electrodes in an alkaline aqueous solution and the corresponding reaction mechanism was experimentally investigated. Both EG and TPA produced hydrogen; however, TPA consumed OH⁻, inhibiting the production of intermediary compounds of EG and causing EG to actively react with H₂O, ultimately leading to enhanced hydrogen production. In addition, the initiation potential of water decomposition of the EG and TPA alkaline aqueous solution was 1.0 V; when 1.8 V (vs. RHE) was applied, the hydrogen production reached 440 mmol L⁻¹, which was substantially greater than the hydrogen production rate of 150 mmol L⁻¹ during water decomposition.