Provided is a technology for, in a battery packaging material having a base material layer including at least a polyester film layer and a polyamide film layer, effectively suppressing delamination of the base material layer in hot and humid environments. The battery packaging material is formed of a laminate having at least a base material layer, an adhesive layer, a barrier layer, and a thermally fusible resin layer in this order, wherein the base material layer includes a first adhesive layer between a polyester film layer and a polyamide film layer, and the base material layer contains an ultraviolet absorber.