The invention discloses a vacuum circuit breaker, and the circuit breaker comprises a circuit breaker body and a chassis truck. The circuit breaker body is disposed on the chassis truck, and the chassis truck comprises a handle and a screw. The handle is rotated to drive the screw so as to drive the whole vacuum circuit breaker to move. The chassis truck also comprises wheels, and the wheels are driven by a transmission shaft to move. The vacuum circuit breaker is enabled to steadily roll on a rail through the wheels. Because a special wheel structure is employed, the vacuum circuit breaker can enter and leave an installation room of the vacuum circuit breaker, achieves the good protection of the mechanical performances of the vacuum circuit breaker body, and prolongs the service life.