The present invention provides a power information network security warning information false alarm judgment method and system. The method includes the following steps that: warning information is acquired, wherein the warning information includes current warning information and historical warning information before the current warning information; the historical warning information is inputted into a power information network security warning prediction model which is established in advance, so that predicted warning information can be obtained; and when the predicted warning information andthe current warning information are inconsistent, it is judged that power information network security warning information is a false alarm. Compared with the latest prior art, the method and system do not require manual intervention, have high efficiency, can judge the false alarm of security alarm information generated in a network with high accuracy, have high judgment efficiency and can improve the usefulness and stability of security alarms.