The invention relates to a two-piece bottle plug which mainly comprises a plug body and a pressing piece, wherein the plug body is integrally formed in a cup shape and is provided with a barrel part, a top disc and a plurality of rib parts inside the barrel part; the top disc is connected to the opening end of the barrel part; the diameter of the top disc is more than that of the barrel part; theplurality of rib parts protrude radially on the inner wall of the barrel part and are mutually separated without connection; each rib part is provided with a butting part; the plurality of butting parts are positioned on the same circumference and protrude towards the central direction; a top part and a pole are formed on the pressing piece; the pole extends from one surface of the top part; a jacking part and a bucking part are formed on the surface of the pole; and the diameter of the buckling part is less than that of the jacking part. The bottle plug can be easily manufactured so that themanufacturing cost of the bottle plug can be reduced; in addition, when the bottle plug is used at the opening part of a vessel, the opening of the vessel can be closely sealed.