Abstract: In recent years, pulsed arc electrohydraulic discharge (PAED) wastewater treatment technology by using liquid electrical discharge process, produced by high-energy particles, free radical oxidation, ultraviolet radiation, shock pressure wave and multiple effect in sewage and organic harmful pathogens for sterilization and degradation. As a new technology of sewage treatment, the multi electrode pulsed arc discharge system is studied in this paper, and the electric field distribution of different electrode positions during discharge is analyzed. At the same time, the ultraviolet radiation effect under different conditions is studied by experiment. It is found that the multi electrode pulsed arc discharge system has the strongest ultraviolet radiation effect, and the discharge electrode spacing, energy storage capacitance and conductivity affect UV intensity.