The invention discloses an early-warning and processing method for an accident of a power-supply system, which comprises the following links of information collection, acknowledgement and implementation, plan starting, notification, emergency treatment, plan closing, and plan assessment and analysis. The links are realized by an early-warning and processing system for the accident of the power-supply system, which comprises a risk assessment early-warning command service platform, communication service equipment and user terminal equipment. The risk assessment early-warning command service platform consists of a peripheral user interface, an application centre module and a bottom data interface, wherein the peripheral user interface is connected with the user terminal equipment through the communication service equipment; the application centre module is connected with the peripheral user interface and the bottom data interface respectively; and the application centre module receives and processes the data information of the peripheral user interface and the bottom data interface and then sends processed result information to the peripheral user interface or the bottom data interface. By the method, the reliability and the reaction efficiency of a risk assessment, early-warning and processing operation of the power-supply system are improved.