Laminated gasket free from liquid drug leakage. A gasket (13) for a medical syringe, with main body (14) made of elastic material, and film (15) provided on a surface of main body (14). Gasket (13) has a circumferential surface portion (17) for contact with an inner peripheral surface of a syringe barrel (11) and an annular groove (22) formed circumferentially in a surface portion of the film in the circumferential surface portion thereof. Annular groove (22) has outer edge portions (24) provided along opposite edges (23) thereof as projecting from an unprocessed surface portion of the film. Annular groove (22) has a groove formation start point and a groove formation end point connected to each other in a groove connection region. Outer edge portions (24) provided along the opposite edges of the annular groove have a maximum-to-minimum height difference of ≤5 μm in the groove connection region.