The invention provides a fatigue tester suitable for device wire clamps. Two to-be-tested device wire clamps are connected via a wire. The fatigue tester includes a box-shaped frame base, two clampingplates, a pull rod, a sliding base, a transmission rod and a rotating wheel driven by a motor. The two clamping plates correspond to the two to-be-tested device wire clamps one to one. Each clampingplate clamps the corresponding to-be-tested device wire clamp. The two clamping plates include a fixed clamp plate fixed to the top of the frame base and a movable clamping plate arranged on the top of the frame base slidably. The upper end of the pull rod is provided with a movable ring sleeve for allowing the wire to pass therethrough. The lower end of the pull rod is connected with the slidingbase. The sliding base is arranged on the frame base vertically movably. The rotating wheel is provided with an eccentric hole. One end of the transmission rod is connected with the sliding base, andthe other end of the transmission rod is connected with the eccentric hole. The fatigue tester is beneficial to the service performance evaluation, the life assessment, the material plan formulation of the device wire clamps, and has important significance for the reliable operation and accident prevention of a power grid line.