The invention relates to a pull rod assembly and a circuit breaker employing the same. The circuit breaker comprises an arc extinguishing chamber and an operating mechanism, wherein the arc extinguishing chamber is provided with an arc extinguishing chamber pull rod, the operating mechanism is provided with a mechanism pull rod, the mechanism pull rod is in transmission connection with the arc extinguishing chamber pull rod, the two pull rods respectively is provided with an opposite end surface facing the other pull rod, the two pull rods are provided with external threaded rod segments, the rotation directions of external threads of the two external threaded rod segments are same, the two external threaded rod segments are coaxially arranged, and the arc extinguishing chamber pull rod and the mechanism pull rod are tightly in threaded connection by threaded sleeves sleeving the two external threaded rod segments in a screwing way. In the pull rod assembly provided by the invention, the external threaded rod segments of the two pull rods are tightly in threaded connection by the threaded sleeves, the rotation direction of the threads of the two external threaded rod segments are same, and the two pull rods which cannot rotate in a circumferential direction and cannot move in an axial direction are tightly connected by conveniently rotating the threaded sleeves. The pull rod assembly provided by the invention is simple in integral assembly mode and is rapid and convenient to assemble.