This research studying the electromagnetic behavior of the induction furnace when its core is a magnetic material taking into consideration the effect of the non-linear dependence of the magnetic flux induced in it due to the applied magnetizing force. Since the magnetic characteristics are severely affected by temperature rise in a non-linear way, so as the specific electric resistance of the charge material, this work deals with studying the effect of temperature on the non-linear characteristics of a magnetic core simultaneously with that on the specific electric resistance to show the electromagnetic behavior of the furnace during heating operation. The distribution of the current density, flux density and the magnetizing force at different temperatures inside the furnace and on the charge surfaces are determined for different temperatures. Also the flux distribution is plotted at these cases. This study will be the base for future work on the electromagnetic-thermal coupled analysis for the induction furnace.