Eregli Iron and Steel Works Co. (Erdemir) is the largest integrated steel plant in Turkey. In this study, the potential for improving the specific energy use of slab furnace #3 of this plant was analyzed. An energy input and output model was established in order to determine the lost energy in the process. According to the study, energy efficiency of slab furnace #3 was calculated as 64.26%. Even though it seems to be a reasonable efficiency value for a slab furnace, it was noticed that further energy conservation can still be achieved by increasing the temperature of hot charging to the slab furnace and recovering the flue gas sensible heat remaining after the recuperator.