Provided is a molded case circuit breaker with a handle locking apparatus. The molded case circuit breaker comprises a circuit breaker body, and a molded case and a handle which are arranged on the circuit breaker body, and further comprises the handle locking apparatus used for both closing locking and opening locking, wherein the handle locking apparatus is in connection with the molded case of the circuit breaker body through an overall mounting and dismounting mode, and through the connection, the handle of the circuit breaker body is locked at a position where wrong closing is not allowed or a position where wrong opening is not allowed. Since the handle locking apparatus does not establish a connection relation with the handle and employs a structure in which the handle locking apparatus is connected with the molded case of the circuit breaker in an overall mounting and dismounting mode, operation of locking and unlocking is quite convenient, simple, rapid and reliable, locking of a closing state and an opening state is realized by one set of assemblies of the same handle locking apparatus, the manufacturing and application cost of a circuit breaker product can be effectively reduced, the circuit breaker body can be improved as little as possible for adaptation to the locking of the handle through the handle locking apparatus, and the application scope is wide.