The present invention provides a switch cabinet and an operating mechanism thereof. The operating mechanism comprises a transmission main shaft which is provided with a damping cam. The transmission main shaft also comprises a damping rod group which comprises a pressing piece which is in pressing coordination with a set contour of the damping cam and an elastic piece which provides acting force facing the damping cam to the pressing piece. The radii of the set contour corresponding to switch-on and switch-off positions of the transmission main shaft are smaller than the radius of the set contour corresponding to a position between the switch-on and switch-off positions of the transmission main shaft. According to the operating mechanism of the invention, in the process that the damping cam rotates with the switch-on and switch-off of the transmission main shaft, the damping rod group can provide rotational resistance to the transmission main shaft through the pressing coordination with the set contour, thus the switch-on and switch-off speeds are reduced, after the transmission main shaft rotates to the switch-on position, the damping rod group provides acting force for preventing the transmission main shaft from leaving the switch-on position to the transmission main shaft, thus the impact damage of a contact is avoided, and the switch contact can be stably maintained at the switch-off position.