An outer casing material for a battery 4 is provided, wherein an outer layer 11, a metal foil layer 10 and an inner layer 8 are laminated via an adhesive layer 5; the inner layer 8 comprises a sealant layer 8b and a base material layer 8a; the sealant layer 8b is made from a propylene-ethylene random copolymer wherein a melt flow rate at 230° C. thereof is in a range of 3 to 30 g/10 minutes; the base material layer 8a is made of a resin composition wherein a melt flow rate at 230° C. thereof is in a range of 0.1 to 15 g/10 minutes, xylene-soluble component Xs thereof satisfies the predetermined conditions, and the resin composition comprises 50 to 80% by mass of a propylene component (A) and 50 to 20% by mass of a copolymer component (B) which is an elastomer of a copolymer of propylene and ethylene and/or α-olefin having 4 to 12 carbons and includes 50 to 85% by mass of a polymerization unit originated from propylene.