A medical port includes a disc-shaped valve 1 in which an insertion hole is formed in a central portion 1a, a base seat 7 that supports the valve from a lower surface side, and a cover 2 that has a fitting hole exposing an upper surface of the central portion of the valve and covers at least a peripheral edge of the valve from the upper surface side, the fitting hole being formed so that when an inserting body has been inserted into the insertion hole, a fit between the inserting body and the fitting hole can cause the inserting body to be locked against the cover. An annular protrusion 1d is formed in the valve 1, the annular protrusion being continuous in the circumferential direction, and formed in the valve 1 so that in the state in which the inserting body is locked against the cover, the annular protrusion is in contact with an outer circumferential surface of a leading end portion of the inserting body.