The invention discloses a switch-on transmission mechanism and an operating mechanism applying the switch-on transmission mechanism and a breaker applying the switch-on transmission mechanism. The switch-on transmission mechanism comprises poking rods and transmission blocks, wherein the transmission blocks and corresponding moving contacts are fixedly arranged together. The transmission blocks are located below the poking rods and are provided with bearing shoulders facing the poking rods. The poking rods are provided with concave openings with openings facing downwards, wherein the concave openings are used for being matched with the bearing shoulders of the transmission blocks in a jacking mode to push the transmission blocks to drive the moving contacts to move towards fixed contacts so as to achieve switch-on when the poking rods move leftwards. The right ends of the poking rods are provided with a hinge structure for being hinged to a power output shaft of the corresponding operating mechanism. According to the switch-on transmission mechanism, when the switch-on transmission mechanism needs to be disengaged, the concave openings are matched with the bearing shoulders of the transmission blocks in the jacking mode, so that only upward action force needs to be applied on the poking rods to turn the poking rods upwards, and then the concave openings can be separated from the bearing shoulders of the transmission blocks; disengaging is convenient to conduct, the concave openings are formed in the poking rods directly, the bearing shoulders are arranged on the transmission blocks directly, and the switch-on transmission mechanism is simple in structure and convenient to assemble, disassemble and maintain.