PROBLEM TO BE SOLVED: To prevent an expansion portion from buckling even if working stress is applied on a caped portion.SOLUTION: Provided is a bottle can in which a cap is screwed and fastened to a caped portion 12. The caped portion 12 comprises: a male screw portion 9; and an expansion portion 8 having a first peripheral wall portion 8a which is continuously provided in the lower end in a can axis direction of the male screw portion 9 and is gradually increased in its diameter toward the lower part thereof, and a second peripheral wall portion 8c which is continuously provided in the lower end of the first peripheral wall portion 8a via a convex curved surface portion 8b protruded outward in the radial direction and is gradually reduced in its diameter toward the lower part thereof. The first peripheral wall portion 8a has a first straight portion...
