VALVE DEVICE

PROBLEM TO BE SOLVED: To provide a valve device capable of inhibiting self-excited vibrations occuring in a valve element, with a simple configuration.SOLUTION: A valve device is configured to be continuos in a direction in which an upstream flow passage 11 on a fluid inlet side and a downstream flow passage 12 on a fluid outlet side intersect each other via a valve chamber 13, and includes a valve box 10 where a valve seat 15 that is gradually enlarged as it advances downward is provided at an opening 11a of the upstream flow passage 11 of a partition wall 14 that partitions the valve chamber 13, a seatable annular sealing part 21 being provided on the valve seat 15, a valve element 20 configured to be able to advance to and retract from the valve seat 15, and an exciting force reduction means 30 for reducing an exciting force acting on the valve element 20 from the fluid, wherein the exciting force reduction means 30 is provided on at least one of the valve seat 15 and the annular sealing portion 21, and serves as eddy current formation part 90 that produces an eddy current.