To provide a spheroidal-graphite-containing cast iron material excellent in toughness, reduced in weight, and useful as a material for automobile lower suspension arm by regulating respective contents of total carbon, silicon, molybdenum, and copper.

In the cast iron material, prepared by adding, as essential additive components, carbon, silicon, manganese, phosphorus, sulfur, and magnesium and also adding, as selective additive components, molybdenum and copper, the additive quantities of total carbon, silicon, manganese, molybdenum, and copper are regulated, by weight, to 2.5-3.5%, 3.5-4.5%, 0.01-0.6%, 0.05-0.7%, and 0.1-0.4%, respectively.