FUEL CELL GASKET AND METHOD OF BONDING FUEL CELL GASKETS TO AN ELECTROLYTE MEMBRANE

[Object] To provide a bonded sheet that can suppress remaining of bubbles and a sheet-member bonding method that can suppress remaining of bubbles. [Solution Means] A bonded sheet 70 to be applied to an MEA 20 includes gaskets 40 and 60 serving as a first sheet member 71, and an electrolyte membrane 21 serving as a second sheet member 72 stacked on the gaskets. The gaskets each include a first bonded portion 81 where grooves 83 provided in a sheet surface direction at least partly face sheet end portions 73 and 74, and a second bonded portion 82 having no groove. The electrolyte membrane is stacked on the gaskets in the first bonded portion and the second bonded portion.