The invention relates to a switch device and a transmission structure thereof. The switch device comprises an arc extinguishing chamber, an operating mechanism and a transmission structure disposed between the arc extinguishing chamber and the operating mechanism, the arc extinguishing chamber is internally provided with a moving contact, the transmission structure comprises a drive rod having oneend passing through the arc extinguishing chamber to connect with the moving contact to drive closing and opening of the moving contact, the drive rod is hinged with a spacing rod and a power input port configured to drive motion of the drive rod through the same hinge structure, the power input rod has a rotation power input end being in transmission connection with the operating mechanism, theother one end of the spacing rod is hinged on the fixed pedestal, and the drive rod achieves the direct moving output itself by employing at least one set of the three sets between the spacing rod andthe fixed pedestal, between the drive rod and the arc extinguishing chamber and between the drive rod and the spacing rod; and the transmission mechanism is a transmission mechanism in the switch device. The above technical solution solves the problem that the reliability of the switch device is relatively low and the power required for the opening and closing of the operating mechanism is high in the prior art.