PURPOSE: To produce a uniformly fired enameled product for a metallic substrate of specified shape by arranging the substrate with the surface glazed in a metallic case having a draft hole through a support and firing the glazed substrate.

CONSTITUTION: A firing case 1 made from an iron sheet, having an opening 2 on the upper surface and a draft hole 3 in the side face and provided with a carrying handle 4 is prepared, and the opening area ratio of the hole 3 is equalized to the area ratio of the thick part of the product. A washbowl C with the surface glazed is placed in the case 1 through a firing base 5, the case is put in a muffle furnace 6, and the enameled washbowl is fired at 750-850°C for 5-10min. An enameled product, which is uniformly fired regardless of the shape and quality of the substrate, is obtained in this way.