HIGH ELECTRIC RESISTANCE ALUMINUM ALLOY

An aluminum alloy casting having high electric resistance, high toughness and high corrosion resistance and optimally usable in manufacturing of electric motor housings, and a method of manufacturing said aluminum alloy casting are provided. The aluminum alloy casting has a composition including Si:11.0-13.0 mass%, Fe:0.2-1.0 mass%, Mn: 0.2-2.2 mass%, Mg: 0.7-1.3 mass%, Cr:0.5-1.3 mass% and Ti: 0.1-0.5 mass%, with the remainder consisting of Al and unavoidable impurities, wherein the content of Cu as an unavoidable impurity is limited to 0.2 mass% or less. In some cases, heat treatments such as solution heat treatment or artificial aging hardening treatment are performed after casting.