To solve the pollution of bisphenol A (BPA) which was considered as an environmental endocrine, boron-doped diamond (BDD) electrodes were prepared by direct current plasma chemical vapor deposition (DC-PCVD) system. Mechanisms and reaction pathways of electrochemical degradation of bisphenol A (BPA) at BDD electrode was investigated by high performance liquid chromatography(HPLC) and liquid chromatography-mass spectrometer(LC-MS). The results showed that BPA with different initial concentrations were completely mineralized to CO₂ at BDD electrode, following the pseudo-first-order rate kinetics. The apparent reaction rate constant for BPA with initial concentrations of 100 and 10 mg·L-1 were 0.494 and 0.700 h-1, respectively. When the current density was increased from 10 to 40 mA·cm-2, the apparent reaction rate constant and the removal rate were increased by 50.61％ and 11.26％, respectively. Seven intermediate products were detected in the degradation process, and two different degradation pathways were discovered. One pathway was that BPA was decomposed readily into one-ring aromatic compounds first and eventually mineralized by electrolysis to CO₂, another was that both of the aromatic rings in BPA molecular structure underwent ring breakage simultaneously and then continuously oxidized to CO₂ till the end of the reaction.