PROBLEM TO BE SOLVED: To provide a medical stopper capable of sufficiently preventing leakage of liquid such as blood and medicine even when it is finished thin. SOLUTION: The annular end portion of the second medical component, which is placed on the step portion of the first medical component having the cylindrical opening portion provided with the step portion and is opposed to the step portion, is the cylindrical second medical component. It is a medical stopper made of an elastic material that is sandwiched by being pressed by, and seals the opening, and has a disc-shaped puncturing portion corresponding to the opening defined by the opening, and an outer periphery of the puncturing portion. The puncture portion is provided with an annular flange portion that is formed integrally with the puncture portion and projects outward from the puncture portion, and a vertical cross section formed by the inner inclined surface and the outer inclined surface on one surface of the flange portion is formed. A mountain-shaped annular ridge is provided concentrically with the flange portion, and the top of the ridge is located radially outward of the puncture portion so as to face the annular end of the second medical component. The inclination angle of the inner inclined surface is larger than that of the outer inclined surface. Have medical plug body. [Selection diagram] Fig. 1【課題】厚みが薄く仕上がっていても、血液や薬剤などの液漏れの発生を十分に防止することができる医療用栓体を提供する。【解決手段】段差部が設けられた円筒状の開口部を有する第１の医療部品の段差部に載置され、段差部と対向する方向から円筒状の第２の医療部品における円環状端部により押圧されることによって挟持されて、開口部を封止する弾性体製の医療用栓体であって、開口部により規定される開口に対応する円板状の穿刺部、穿刺部の外周に穿刺部と一体的に形成され穿刺部から外方に突出した円環状のフランジ部を備えており、フランジ部の一方側の面上に内側傾斜面と外側傾斜面とによって形成される縦断面が山形形状である円環状の凸条がフランジ部と同心状に設けられ、凸条の頂部が穿刺部よりも半径方向外方で第２の医療部品の円環状端部に対向して位置するように設けられており、内側傾斜面の傾斜角が外側傾斜面の傾斜角よりも大きい医療用栓体。【選択図】図１
