The utility model discloses a guide vane closing system used when a pumped storage unit breaks down. The system comprises a main pressure distribution valve, an accident pressure distribution valve, asegmented closing device and a servomotor, one port of the main pressure distribution valve is connected with a closing cavity of the servomotor through the accident pressure distribution valve, theother port of the main pressure distribution valve is connected with the segmented closing device through an accident pressure distribution valve device, and then the segmented closing device is connected with an opening cavity of the servomotor; according to the utility model, the main pressure distribution valve, the emergency pressure distribution valve and the sectional closing device are controlled; therefore, the hydraulic system utilizes different actuating mechanisms to execute the guide vane closing rules under the corresponding working conditions, the reliability of the correspondingactuating mechanisms is protected by utilizing the mechanical hard loop, the correctness of executing the load shedding guide vane closing rules under the two working conditions is reliably ensured,and the safety of the pumped storage power station is ensured.