Abstract: This invention relates to a sintered alloy of a boride containing iron consisting essentially of a hard phase composed mainly of iron boride or a multiple boride containing iron in which a part of iron boride is substituted by a non-ferrous boride or multiple boride and a metal phase composed of at least one metal selected from Cu, Co, Ni, Fe, Cr, Mo, W, Ti, Zr, Hf, V, Nb, Ta and alloys composed mainly of these metals, wherein the boron content is 3 to 20% by weight, and to a method of making such sintered alloy. The sintered alloy of this invention has a hardness higher than that of high speed steel and has such high hardness and strength that it is comparable to alloys of cemented carbide, and it is characterized in that it has a good corrosion resistance at room temperature, a high oxidation resistance at high temperatures, a high hardness and a high strength, and that it is cheaper and lighter than cemented carbide.