An aluminum alloy for microporous hollow shape material use constituted by an aluminum alloy which has excellent corrosion resistance and extrudability which keeps down the content of Cu which poses a problem in intergranular corrosion resistance, which maintains the natural potential noble, which adds transition metals which do not obstruct the extrudability is provided, that is, an aluminum alloy which has a chemical composition which contains, by mass %, Fe: 0.05 to 0.20%, Si: 0.10% or less, Cu: 0.15 to 0.32%, Mn: 0.08 to 0.15%, Zr: 0.05% or less, Ti: 0.06 to 0.15%, Cr: 0.03% or less, and balance: Al and unavoidable impurities and has an amount of gas in the alloy billet of 0.25 cc/100 g or less, and a method of production of an aluminum alloy which, produces a DC cast billet.