The invention discloses a pumped storage power station excitation system black start control circuit and a control method thereof, and relates to the technical field of hydropower station black start. Through the control circuit and the control method, after a hydro-generator is shutdown due to failure, automatic black start of the hydro-generator can be conducted in a specified time, and power supply to a power system is thus restored quickly. The control circuit and the control method are of high reliability and good safety. The control circuit comprises a standby power supply, a monitoring system, an excitation system and a hydro-generator, wherein the standby power supply, the excitation system and the hydro-generator are connected with the monitoring system, and the standby power supply and the hydro-generator are connected with the excitation system. According to the invention, when a large-area blackout accident occurs to a power system powered by a hydro-generator, a generator set with black start capability is used to start power generation and further drive a hydro-generator set without black start capability to generate power so as to gradually restore the whole power system.