Abstract: A fluid coupling comprising a pump having a pump shell and a plurality of impellers arranged in the pump shell, a turbine having a turbine shell arranged to be opposed to the pump and a plurality of runners arranged in the turbine shell, and a baffle mechanism arranged in a fluid circulation passage formed by the pump shell and the turbine shell, wherein the baffle mechanism comprises a first baffle plate having a plurality of first openings, a second baffle plate that has a plurality of second openings and is disposed in such a manner as to overlap with the first baffle plate and as to be allowed to rotate relative thereto, and a centrifugal operation means for turning the second baffle plate relative to the first baffle plate in response to the rotational speed of the first baffle plate.