Abstract: Because of the great difference in temperature,steel ingot in electroslag casting process is easy to cause the thermal stress,which is difficult to measure.In view of this characteristic,the steel ingot stress field with different depth of slag pool was simulated by the finite element analysis software ANSYS.Then the basic logarithmic relation between equivalent stress and axial stress both gained from steel ingot top-down surface in axial direction was found.The result of the simulation tallies with the practice.This model can be used to predict the condition of the steel ingot stress field,and to direct practical production.