An aluminum alloy sheet having a heat dissipation characteristic that is applicable to a large-size lithium ion battery container, excellent in formability and shape freezability and excellent in laser weldability is provided. An aluminum alloy sheet comprising a cold rolled, annealed material containing Fe: 0.05 to less than 0.3 mass %, Mn: 0.6 to 1.5 mass %, and Si: 0.05 to 0.6 mass %, has a balance of Al and impurities Cu: less than 0.35 mass % and Mg: less than 0.05 mass %, has a conductivity exceeding 45% IACS, has a 0.2% proof strength of 40 to less than 60 MPa, and displays a 20% or more value of elongation is also provided. An aluminum alloy sheet comprising an as-cold-rolled material having a conductivity exceeding 45% IACS, a 0.2% proof strength of 60 to less than 150 MPa, and displaying 3% or more value of elongation is also provided.