A spout cap (3, 3A, 3S) comprising: a cap body that is an injection molded article made of resin, and is configured to tubularly surround a mouth portion of a spout body; and a sealing film that is a laminated film, and is bonded to one side in a tubular penetration direction of the cap body and can be thermally bonded to a tip surface of the mouth portion to seal the mouth portion of the spout body, wherein the cap body includes a tubular body portion, and a tab portion disposed outside in a caliber direction of the body portion, the tab portion includes a tab base portion that projects outward in the caliber direction from the other side in the penetration direction of the body portion, and a tab body portion that extends from the tab base portion toward one side in the penetration direction and faces the body portion on an outside in the caliber direction, and the tab body portion is annular and can be deformed outward in the caliber direction of the body portion with respect to the tab base portion, characterized in that the body portion includes a pair of breaking portions that breakably joins both sides in a circumferential direction with respect to the tab base portion and extends toward one side from the other side end in the penetration direction of the body portion, a pair of first slit portions extending in the circumferential direction from the one side end of the pair of breaking portions, and a pair of intermediate joint portions (57, 58) that joins a portion on the one side and a portion on the other side in the penetration direction with the pair of first slit portions as boundaries, between the pair of first slit portions, and the intermediate joint portion on an opposite side of the tab portion out of the pair of intermediate joint portions (57, 58) is a hinge portion. the cap body includes a tubular body portion, and a tab portion disposed outside in a caliber direction of the body portion, the tab portion includes a tab base portion that projects outward in the caliber direction from the other side in the penetration direction of the body portion, and a tab body portion that extends from the tab base portion toward one side in the penetration direction and faces the body portion on an outside in the caliber direction, and the tab body portion is annular and can be deformed outward in the caliber direction of the body portion with respect to the tab base portion, characterized in that the body portion includes a pair of breaking portions that breakably joins both sides in a circumferential direction with respect to the tab base portion and extends toward one side from the other side end in the penetration direction of the body portion, a pair of first slit portions extending in the circumferential direction from the one side end of the pair of breaking portions, and a pair of intermediate joint portions (57, 58) that joins a portion on the one side and a portion on the other side in the penetration direction with the pair of first slit portions as boundaries, between the pair of first slit portions, and the intermediate joint portion on an opposite side of the tab portion out of the pair of intermediate joint portions (57, 58) is a hinge portion.