Silicone cover

The utility model provides a silicone cover. The silicone cover comprises a hollow cylindrical cover body; one end of the cover body is open, while the other end of the cover body is closed; the cross sectional area of the cover body is gradually reduced from the closed end to the open end; an annular groove of which the cross sectional area is circular-arc-shaped is formed inside the cover body along the edge of the closed end; a hollow cylindrical sealing ring extending from the closed end to the open end is fixedly arranged inside the cover body; the sealing ring is arranged separately from the inner wall of the cover body; a gap between the sealing ring and the inner wall of the cover body forms a sealing cavity for sealing the mouth of a bottle; the sealing cavity is communicated with the annular groove. As the cross sectional area of the cover body is gradually reduced from the closed end to the open end, the cover body is capable of tightly covering the mouth of the bottle and the airtightness between the cover body and the mouth of the bottle can be improved; as the annular groove inside the cover body is matched with the flange at the mouth of the bottle, the airtightness between the cover body and the mouth of the bottle can be improved, and the cover body also can be prevented from dropping from the mouth of the bottle.