An embodiment of the invention provides a pumped storage unit run-out protection and monitoring system. The system comprises a sensor, a run-out protection device and a monitoring device, wherein the sensor is used for collecting the operation parameters of a pumped storage unit in real time and sending the operation parameters to the run-out protection device, the run-out protection device is used for sending the operation parameters to the monitoring device, the monitoring device is used for analyzing the operation parameters to get the run-out parameters of the pumped storage unit and sending the run-out parameters to the run-out protection device, and the run-out protection device is further used for adjusting the initial alarm value and the initial stop value of run-out under steady working condition of the pumped storage unit according to the run-out parameters to get a new alarm value and a new stop value. According to the scheme, the alarm value and the stop value of run-out under steady working condition of the pumped storage unit can be automatically adjusted and updated as the operation condition of the pumped storage unit changes, so that the alarm value and the stop value better match the actual operation state of the pumped storage unit, the accuracy of the alarm value and the stop value is improved, and the reliability of the run-out protection device is improved.