A circuit breaker includes a housing, wiring boards and terminals disposed within the housing, wherein the terminal comprises a screw, a press board and a wire trap provided with a incoming line hole and a wiring space; the screw passes through a threaded hole on the top end face of the wire trap to contact the press board which is able to lift up and down and is embedded in the wire trap; the wiring board traverses the wire trap, and divides the wiring space of the wire trap into two independent wiring spaces; a first line hole is provided on the housing at a position above the screw of the terminal; and the press board and the wire trap perform a relative displacement with the wiring board under the action of the screw, to compress the two independent wiring spaces so as to realize the connection between wires. In the circuit breaker, with the wiring board as a boundary, the wiring space of the wire trap is divided into two independent wiring spaces, realizing a hybrid junction of commonly used wires while realizing the hybrid junction wiring function of single-strand wires with different diameter.