The invention relates to a grounding switch, an operating mechanism thereof and a transmission structure. The grounding switch comprises the operating mechanism. The operating mechanism comprises a driving device and the transmission structure. The transmission structure comprises a crank. A connecting rod is hinged to a rotary end of the crank, a hinged joint of the crank and the connecting rod is positioned in the middle of the connecting rod, one end of the connecting rod can move on guide tracks, the other end of the connecting rod is hinged to a movable contact, joints of the connecting rod and the guide tracks, a hinged joint of the connecting rod and the movable contact and the rotation center of the crank are positioned on the same circle, the hinged joint of the crank and the connecting rod is used as a circle center of the circle, and the extension directions of the guide tracks are perpendicular to movement paths of the movable contact. The grounding switch, the operating mechanism and the transmission structure have the advantages that movement trajectories of an end of the connecting rod are constrained, accordingly, movement trajectories of the hinged point of the connecting rod and the movable contact can be constrained, the movable contact can be prevented from being inclined in a movable contact seat when the movable contact is driven by the connecting rod to carry out reciprocating movement, and the phenomenon of clamping stagnation between existing movable contacts and existing movable contact seats due to inclination in high-speed movement procedures canbe prevented.