Provided is a medical valve of a novel structure, which is able to more reliably support an outer peripheral part of an elastic valve body with respect to a housing, and prevent a problem of the elastic valve body becoming dislodged inward. A medical valve (10) includes an elastic valve body (16) with annular grooves (76, 74) formed thereon and a tubular support part (70) formed at an outer peripheral side of an annular joining part (72) positioned between the annular grooves. Inside and outside holding parts (20, 18) engage the annular grooves (76, 74) provided to the valve inside and outside surfaces of the annular joining part (72). The outside holding part (18) and inside holding part (20) are provided to an opening member (12), and with the tubular support part (70), a part projecting inward in an axial direction (82) is sandwiched and supported between the inside holding part (20) and outside holding part (18).