A two-dimensional mathematical heat transfer model for the prediction of temperature distribution within the slab has been developed by considering the thermal radiation in the walking-beam-type reheating furnace chamber and transient heat conduction in the slab, respectively. The steel slabs are heated up through the preheating, heating, and soaking zones in the furnace. Heat transfer characteristics and temperature uniformity of the slab is investigated by changing hot gas temperature. Comparison with the in-situ experimental data show that the present heat transfer model works well for the prediction of thermal behavior of the slab in the reheating furnace. The skid mark severity decreases with an increase in hot gas temperature.