The invention provides a system and method for flue gas waste heat efficient recycling of a steel making electric furnace and belongs to the technical field of waste heat recycling of the metallurgical industry. The waste heat recycling system comprises a waste heat recycling device, a water supplementing system and a flue gas dedusting system and the like. After high temperature flue gas coming out of the electric furnace first passed a heat insulation settling chamber so as to remove large particle dust in flue gas, the flue gas enters a waste heat boiler to be fully cooled and then enters a bag-type dust collector to be dedusted, the flue gas is discharged through a chimney after being dedusted, and discontinuous and fluctuant saturated steam generated by the boiler is continuously and stably output after being regulated through a heat accumulator. The system is further provided with a flue gas bypass. When the waste heat boiler has a failure, the waste heat boiler is split, so that the system stability is improved, the flue gas waste heat is fully recycled, and the waste heat recycling efficiency is improved.