PURPOSE: To provide a fluid type retarder control device which can not only prevent the reduction of the durability of a sliding friction part resulting from the mixture of a foreign matter in an operating liquid, but also can secure a necessary flow rate of the operating liquid, can suppress an excessive temperature rise of the operating liquid in a fluid type retarder, and can release the reduction of the durability of a seal member made of a rubber.

CONSTITUTION: A fluid type retarder 11 provided to a rotary shaft 10 rotating together with a wheel, having a rotor 16 and a non-rotating stator 15, and filling an operating liquid; a clutch device 13 to connect or disconnect the rotor 16 and the rotary shaft 10; and a pump 22 provided to a passage 21 to connect between the operating liquid inlet 11a and the operating liquid outlet 11b of the fluid type retarder 11, and to circulate the operating liquid; are provided. And a flow rate control device 28 having a valve 27 to open the passage 21 when the upstream side is made more than a specific pressure, and a filter 26 to remove the foreign matter in the passage 21, in parallel is provided to the passage 21.