Abstract: Provided is a plug assembly for a beverage container, exhibiting a favorable pourability without hindering a compactness. The assembly includes: an outer plug fitted into an upper opening of a container body and having an outflow passage therein; and an inner plug fitted into an upper opening section of the outer plug. Provided on the inner circumferential surface of the outer plug is a female screw having a thread continuous in the radial direction and used to attach the inner plug. Provided on the outer circumferential surface of the inner plug is a male screw corresponding to the female screw. Flow passages are formed by vertically cutting out at least a part of the male screw, and provided on the upper regions of the flow passages are control walls linearly slanting upward and outward. A stable screwed state can be consistently maintained regardless of the locations of the flow passages.