The invention relates to a middle-arranged high-voltage circuit breaker operating mechanism and a high-voltage circuit breaker in the field of high-voltage electrical appliances. The middle-arranged high-voltage circuit breaker operating mechanism comprises three crank arm boxes which are sequentially arranged, wherein the crank arm boxes which are arranged at the middle positions in the arrangement direction of the crank arm boxes are middle crank arm boxes, each crank arm box is provided with a pole mounting structure for mounting a corresponding unipolar pole, a transmission shaft which isperpendicular to the arrangement direction of the crank arm boxes is arranged in each crank arm box, the middle-arranged high-voltage circuit breaker operating mechanism further comprises a driving motor which is used for driving the transmission shafts in the middle crank arm boxes to rotate, and an output shaft of the driving motor and the transmission shafts in the middle crank arm boxes are coaxially arranged and are in transmission connection. During the use process, the transmission shafts in the other two crank arm boxes rotate along with the transmission shaft in the middle crank arm box, so that the switching on-off of the circuit breaker is achieved; compared with the prior art, the transmission path between the driving motor and the transmission shafts in the middle crank arm boxes is shorter, the transmission structure is simple, the transmission efficiency is higher, and the probability of fault occurrence is reduced.