In a conventional laminated gasket production method, when a product of a laminated gasket is demolded from a mold, the product is rubbed against the mold and, therefore, minute scratches are formed on a surface of the laminated gasket. These minute scratches are liable to prevent reliable sealing of a liquid drug. The present invention is a method for producing a gasket to be used for a medical syringe and is characterized by including the steps of: preparing a gasket molding mold； molding a gasket (13) having a circumferential surface portion (17) in the mold with the gasket (13) being laminated with a lamination film (15)； and demolding the gasket (13) from the mold, and then forming a groove (22) only in the lamination film (15) circumferentially of the circumferential surface portion (17) of the gasket (13).
