PURPOSE: To prevent curving of the cut end faces of an ingot and to obtain the cut ingots having high quality in high yields in the stage of cutting the central part of the hot ingot longitudinally by specifying the temp. difference between the central part and the surfaces in both side parts.

CONSTITUTION: Both side parts 1, 1' of an ingot after casting are insulated of heat by shielding or winding of heat insulating materials until the cutting stage. The parts 1, 1' are heated just prior to cutting. The ingot is cut as early as possible after the end of casting. The temp. during cutting is controlled in such a way that the temp. difference between the central part 2 of the ingot and the parts 1, 1' is kept at ≤400°C until the cutting is completed. Then, even if the continuous casting ingot is hot split longitudinally, the cut end faces retain without recessing or other deforming and the cut ingots having high quality are produced in high yields.