An aluminum alloy sheet contains 0.1% to 0.4% by mass of Cu, 0.5% to 1.5% by mass of Mg, 0.5% to 1.5% by mass of Mn, 0.2% to 0.7% by mass of Fe, and 0.1% to 0.3% by mass of Si. The number density of Al--Mn--Fe--Si-based intermetallic compound having a maximum length of 8 to 15 .mu.m per unit area is 179 grains/mm.sup.2 or less. An oxide film having an average thickness of 30 nm or less is formed on the surface of the aluminum alloy sheet. The arithmetic average roughness Ra of the surface of the aluminum alloy sheet is 0.30 to 0.45 .mu.m.