To provide a gasket arranged between two elements to seal by pressing pressure and capable of suppressing breakage by pressing pressure to enable regulation of dimension in the lateral direction.

This gasket 20 for sealing a section between a first separator 14 and a second separator 16 facing it has a first layer 22 attached to the first separator 14 and constituted by a hard material, a second layer 24 integrated with and laminated on the first layer 22, having a projecting tip part 28 coming into contact with the second separator 16, and constituted by a soft material, and an absorption part 26 provided in a central section between the first layer 22 and the second layer 24 to absorb a deformed part of the soft material caused by pressing pressure P between the first separator 14 and the second separator 16.