The invention provides a remote power-failure restarting method and a device. The remote power-failure restarting device comprises a signal processing chip, a relay driving chip and a relay, wherein the output end of the signal processing chip is connected with the input end of the relay driving chip; the output end of the relay driving chip is connected with a coil of the relay; and one end of the normally open contact of the relay is connected with a power supply, and the other end is connected with a power supply end required to be cut off for restarting the device. The signal processing chip receives a power-failure restarting command sent by the external world, and analyzes the power-failure restarting command to obtain a branch required to be cut off for restarting the device; the signal processing chip outputs a driving command to the relay driving chip; the relay driving chip controls the closure of the normally open contact of the relay after breaking according to the driving command, so that the power-failure restarting control to the device is realized, workers are not required to implement the power-failure restarting to the device in scene, the workload is reduced, and the time is saved.