The present invention provides a gasket material to be placed between two opposing faces to provide a tight closure between them. The gasket material of the present invention, wherein an adhesive layer comprised of a cured product obtained by reacting a polyoxyalkylene polymer having at least one alkenyl group in each molecule with a compound containing two or more hydrosilyl groups on average in each molecule is formed on both surfaces of a substrate sheet, is superior in elasticity and compaction property, shows superior adhesion to various materials, does not cause cohesive failure during detachment and is superior in removability. Therefore, a superior sealing effect lasts for a long time, the gasket material can be removed without leaving residues of the adhesive layer on an adherend after removal, and workability including removal of the gasket material can be improved.