Abstract: A mixing/charging port for medical treatment capable of reliably mixing/charging solutions or collecting the solutions in a medical instrument equipped with a solution feed passage, comprising a disc-like valve (1) having an insertion hole at the center, a cover (2) for restraining the valve (1) by covering at least the upper part of the periphery of the valve (1) with the center on the front surface side of the valve (1) left uncovered, and a round fitting hole (6) formed at the center of the cover (2) as anchor means for anchoring an insertion member to a mixing/charging port, the fitting hole (6) and the insertion member being so fitted to each other as to be capable of anchoring.