The present invention relates to an electric power automation system data emergency transmission method and device. The method and device are characterized in that: a power grid dispatching center, a centralized control station and a transformer substation are respectively provided with a master station communication system and a factory station communication system, and the public network wireless communication between the master station communication systems and the factory station communication systems is realized. The factory station communication systems and the transformer substation RTU are connected with a synthesis device and are configured to transmit the collected data to the master station communication systems through wireless communication; and the master station communication systems are effectively connected with the power grid dispatching center and the EMS front-end processor of the centralized control station and are configured to transmit the received data to an SCADA system. The electric power automation system data emergency transmission method and device are able to realize the data emergency transmission of the power grid in the condition that the data remote transmission link is abnormal or has faults, or a telecontrol channel does not have the real joint debugging condition during building or expanding the system.