A power network safety defense warning system comprises a safety supervision module configured to monitor safety state information of a network host in a power network; a region supervision module configured to collect network management configuration information of an available communication node and detect the real-time communication state of a corresponding network; a collaborative defense module configured to provide safety defense for the power grid terminal edge access; a safety analysis module configured to perform network safety analysis for each network; and a real-time warning moduleconfigured to perform real-time warning and display. The power network safety defense warning system can achieve omnibearing individual monitoring, the whole-region monitoring, collaborative defense,safety analysis and real-time warning for the power network so as to roundly protect the safety of the whole power network in a three-dimensional mode.