The invention discloses an eddy current retarder of a magnetic track of a railway vehicle, comprising a permanent magnet, an iron core and a magnet yoke. The iron core is provided with a winding, the magnet yoke is near to an iron rail, the permanent magnet, a magnet insulation material and a magnet conduction material are connected and abreast arranged at one end of a support, the other end of the support is connected with a piston, pistons are symmetrically placed at the two ends of an air cylinder, the air cylinder is connected with a movable groove, stator iron cores are embedded at the two sides of the movable groove, one end of the iron core is connected with the magnetic yoke, and one end of the magnet yoke is embedded in the movable groove. The invention integrates the advantages of the eddy current retarder and a permanent magnet eddy retarder, realizes closed magnetic circuits of the eddy current retarder and the permanent magnet eddy retarder through moving the support with the permanent magnet, the magnet insulation material and the magnet conduction material, realizes the switch between two operation states of the eddy current retarder and the permanent magnet eddy retarder on the railway vehicles, adjusts retardation brake torque, reduces the manufacture and operation cost, and can be applied to vehicles of urban light rails, high speed trains, magnetic suspension trains and the like.