The invention relates to a plug-in distribution box multifunctional interlocking mechanism. A clamping plate is in the vertical position when a cabinet door is open, a swing arm is limited to rotate upwards, a switch of a molded case circuit breaker is not pushed to close, when the cabinet door is closed, the clamping plate is pushed to rotate away from the vertical limit position by a top plate,a swing arm can rotate upward to push the switch of the molded case circuit breaker to close, moreover, an interlocking plate and a dial rod are utilized to drive a main shaft to a bus contact on/offoperating mechanism to rotate, and a bus plugging state is locked. In the closing process, a hook rotates upwards with the swing arm and is inserted into a slot plate for matching limit, the cabinet door cannot be opened; through one operation, double interlocking functions of interlocking of the cabinet door switch and the molded case circuit breaker and interlocking of the cabinet door switch and a bus power supply can be completed at the same time, the structure is simple and compact, operation is convenient, the size is small, and the multifunctional interlocking mechanism is safe and reliable.