The invention relates to a high potential electron plate of a thyristor valve. The high potential electron plate of the thyristor valve comprises a power supply converting module, a power supply state detecting module, a valve voltage detecting module, a power amplifying module, a light receiving module, a signal returning and light emitting module and a logic module. Compared with the conventional similar electron plate, the high potential electron plate of the thyristor valve is innovated and updated in the aspects of a power supply energy-obtaining method, valve voltage detection and the logic module, wherein the power supply energy-obtaining method is updated to high-frequency energy transmission from a voltage energy-obtaining method; the valve voltage detection is updated to bidirectional voltage detection from unidirectional voltage detection; the logic module is updated to a programmable logic circuit taking CPLD as a core from a circuit consisting of universal integrated chips. Therefore, one triggering command can trigger two thyristor elements with the same cathode and perform corresponding detection to facilitate the subsequent development, and the high potential electron plate can be widely applied in photoelectric triggering systems of various thyristor valves.