An object is to provide a method for producing a port that can shorten the time for production. Provided is a method for producing a port including: sealingly inserting a sealing plug, through which a hollow needle can be pierced, into a part to be sealed of a port body, wherein 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; a connection part that has a tubular shape, and is continuous with the first end of the part to be sealed; and the 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; fitting a fitting part of a pulling-out prevention member into the part to be fitted, wherein the pulling-out prevention member includes: a body part that has a first surface and a second surface opposite to the first surface, and the fitting part that is continuous with the body part; and laying the body part on the sealing plug.