An object of the present invention is to provide a gasket capable of maintaining a surface pressure for a long period of time while securing sealing performance and improving durability and a manufacturing method thereof. A gasket includes a first annular portion which is formed by a metal wire woven fabric and has a seal target hole and a main body portion which is formed by a metal wire woven fabric and is in contact with an outer peripheral edge of the first annular portion, in which a metal wire of the metal wire woven fabric and a metal wire of the metal wire woven fabric are entangled so that the first annular portion and the main body portion are joined to each other and a gap between the metal wires forming the first annular portion is sealed by a resin.