Exterior material for all-solid-state battery, and all-solid-state battery

Provided is an exterior material for an all-solid-state battery capable of preventing the occurrence of defective parts such as breakage. The present invention is an exterior material for an all-solid-state battery for sealing a solid-state battery main body (5), the exterior material being provided with a base material layer (11), a metal foil layer (12) laminated on the inner surface side of the base material layer (11), and a sealant layer (13) laminated on the inner surface side of the metal foil layer (12). A resin heat-resistant gas barrier layer (21) is provided between the metal foil layer (12) and the sealant layer (13), and the Young's modulus at 90 DEG C of the heat-resistant gas barrier layer (21) is 1 GPa or more in both MD and TD. 本发明提供能够防止产生破损等缺陷部的全固态电池用外装件。本发明以用于将固态电池主体5封入的全固态电池用外装件作为对象，所述全固态电池用外装件具备基材层11、层叠于基材层11的内表面侧的金属箔层12、和层叠于金属箔层12的内表面侧的密封剂层13。在金属箔层12与密封剂层13之间设置有树脂制的耐热气体阻隔层21，耐热气体阻隔层21的90℃时的杨氏模量在MD及TD上均为1GPa以上。