A melt of a Cu-based alloy containing 2 to 6% (% by weight, the same shall apply hereinafter) of Ag and 0.5 to 0.9% of Cr are solidified by casting, and the solidified article after subjecting to a homogenizing heat treatment is subjected to hot-working. The hot-worked article is subjected to a solution treatment, the article is subjected to cold-working or warm-working by forging or rolling, and then the formed article is subjected to an aging treatment to obtain a metallic material capable of manufacturing a high strength and high thermal conductive metal formed article at a low price, regardless of the geometry, and a method of manufacturing the metal formed article using the same.