Abstract: In this study, the thermal resistance of plates is represented by both the thermal resistance of cylinders in the radius direction and cavity to establish the cross section temperature theory and the numerical heat transfer models in steel cables without protection material exposed to fire by analytical method based on heat transfer theory and using ABAQUS software to simulate the heat transfer. It is compared with the cross section temperature field between steel cables and steel bars. It is indicated that the size of cable sections and the cavity radiation have strong effects on the temperature history of steel cables, and the cavity radiation speeds up the temperature in steel cables. It suggests that the cross section temperature calculation formula in steel cables based on the heat transfer theory and the numerical simulation can accurately determine the extents of deterioration of steel cable material properties during the fire heating process and accurately evaluate the fire resistance capacity of steel cables.