An object is to provide a a port that is capable of securely preventing pulling-out of a sealing plug from a port body. Provided is a a port including: a sealing plug through which a hollow needle can be pierced; a port body having a hollow structure with the sealing plug disposed therein; and a pulling-out preventing member to be attached to the port body. The port body includes: a part to be sealed that has a tubular shape with a first end and a second end opposite to the first end, and is configured so that the sealing plug is sealingly inserted into the part to be sealed; a connection part that has a tubular shape, is continuous with the first end of the part to be sealed, and has an outer periphery connected to the bag body to be filled with a medical liquid; and a part to be fitted that is formed in any one of an inner peripheral surface of the part to be sealed, an outer peripheral surface of the part to be sealed, and the second end of the part to be sealed. The pulling-out preventing member includes: a body part that has a first surface directed toward the first end of the part to be sealed within the part to be sealed; a restriction part that is formed on the first surface of the body part and restricts movement of the sealing plug toward the second end of the part to be sealed; and a fitting part that comes into fitting engagement with the part to be fitted of the port body.