Molded-case circuit breaker

The utility model discloses a molded-case circuit breaker comprising a pedestal, a seat cover arranged on the pedestal and an accessory cover arranged on the seat cover. The seat cover is provided with a handle aperture setting zone. A position, corresponding to the accessory cover, of the handle aperture setting zone is provided with a handle aperture for an operating handle to go through. The seat cover is provided an accessory cavity used for setting accessories of a circuit breaker. The bottom portion of the accessory cavity is provided with a through hole. The molded-case circuit breaker also comprises a blocking member used for blocking the through hole and arranged in the accessory cavity when the circuit accessories are not arranged in the accessory cavity. The blocking member is detachably arranged in the accessory cavity. According to the utility model, when the circuit breaker accessories are not arranged in the accessory cavity, the blocking member arranged in the accessory cavity can block the th