The invention provides an electric melting furnace, an electric melting method and a method for producing rock wool by using electric smelting red mud, and relates to the field of high-temperature melting. An electric melting furnace body is in structure matching with an ignition device, and electric discharging points of graphite electrodes of the ignition device are respectively and electricallyconnected with resistance wires; an electrode automatic adjusting mechanism comprises an electrode lifting mechanism, the electrode lifting mechanism is electrically connected with the three-phase graphite electrodes, and the electrode lifting mechanism drives the three-phase graphite electrode to ascend and descend; and the electric melting furnace body is provided with channels for moving the graphite electrodes. According to the technical scheme, the contact area between the three-phase graphite electrodes and a molten liquid can be adjusted, and the voltage can be converted under an on-load condition, so that electric arc heat is concentrated, the electric arc is stable, and the phenomena of large fluctuation of voltage and current, unstable arc burning, short circuit and arc breakingare avoided. Impact on the power grid in an implementation process is avoided, and no harmonic pollution is caused.