Provided is a non-aqueous electrolyte battery including: a power-generating element; and a battery container configured to house the power-generating element. The power-generating element includes: a positive electrode; a negative electrode; a separator interposed between the positive and negative electrodes; and a non-aqueous electrolyte. The battery container includes: a battery case having an opening; a sealing plate configured to close the opening; and a gasket interposed between the battery case and the sealing plate. The gasket includes a PFA resin being a copolymer of tetrafluoroethylene and perfluoroalkyl vinyl ether, and at least a part of the PFA resin has undergone a melting treatment 2 to 20 times to be a first component. The melting treatment includes heating the PFA resin to a melting temperature of 310° C. to 450° C. for melting and then cooling the PFA resin back to a solid.