PURPOSE: To prevent the sticking and impregnation of water drops and moisture and the intrusion of moisture and to obtain a good ingot having no foam by drying an ingot case for molding which temperates an alloy in a molten state and molds the same to a specified shape then using such ingot case.

CONSTITUTION: Various metals are melted to attain prescribed component ratios and the melt is poured into the ingot case, by which the alloy is molded. The ingot case is formed of a carbon stock and is preheated prior to pouring of the molten alloy therein; further dry air of a high temp. is injected thereto to thoroughly dry the ingot case. The ingot case is stored in a storage case having the atmosphere of the dry air when not needed. The ingot case in the thoroughly dried state right after the use for ingot molding is housed in the storage box in the stage of using the storage box. The remaining of foam in the ingot solidifying in the ingot case is, therefore, obviated and the extremely good product is obtd. A yield is thus improved.