Miniature circuit breaker arc extinguish chamber structure

An arc extinguish chamber structure of a miniature circuit breaker comprises a mounting support, a run-on plate, a plurality of first arc extinguish plates and a plurality of second arc extinguish plates are arranged in the mounting support, the first arc extinguish plates and the second arc extinguish plates are arranged at intervals, openings are formed in the upper ends of the first arc extinguish plates and the upper ends of the second arc extinguish plates, arc extinguish ends are arranged in the middles of the bottoms of the openings, and arc extinguish holes are formed in the arc extinguish ends. The arc extinguishing end of the first arc extinguishing grid piece is higher than the arc extinguishing end of the second arc extinguishing grid piece, and an arc extinguishing path which is bent up and down is formed in the installation support. Compared with the prior art, the miniature circuit breaker arc extinguish chamber structure has the advantages that since the arc extinguish ends of the arc extingui