A management system for a component mounting line in which multiple devices that perform multiple processes for producing an electronic component mounting board on which an electronic component is mounted in an order are disposed along a conveyance path of the electronic component mounting board, the system comprising: a management computer that is connected to the multiple devices configuring the component mounting line through a communication network and manages the component mounting line, wherein a CPU box as a control entity and an internal device configured to communicate with the CPU box are attached to each device configured to configure the component mounting line, a non-volatile storage medium of the CPU box of each device configured to store unique identification information assigned to a communication device of the internal device communicating with the CPU box, and a non-volatile storage medium of the management computer configured to store management data of each device in association with the unique identification information of an internal device side of each device configured to configure the component mounting line, and the CPU box of each device is further configured to - communicate with the communication device of the internal device, - obtain the unique identification information of the internal device side, - compare the unique identification information of the internal device side with the storage data of the unique identification information of the internal device side read from the non-volatile storage medium of the CPU box, and, - if both do not match each other based on the comparing, determine that the CPU box or the communication device of the internal device has been replaced, and obtain the management data of the device stored in association with the unique identification information of the internal device side from the non-volatile storage medium of the management computer. a management computer that is connected to the multiple devices configuring the component mounting line through a communication network and manages the component mounting line, wherein a CPU box as a control entity and an internal device configured to communicate with the CPU box are attached to each device configured to configure the component mounting line, a non-volatile storage medium of the CPU box of each device configured to store unique identification information assigned to a communication device of the internal device communicating with the CPU box, and a non-volatile storage medium of the management computer configured to store management data of each device in association with the unique identification information of an internal device side of each device configured to configure the component mounting line, and the CPU box of each device is further configured to - communicate with the communication device of the internal device, - obtain the unique identification information of the internal device side, - compare the unique identification information of the internal device side with the storage data of the unique identification information of the internal device side read from the non-volatile storage medium of the CPU box, and, - if both do not match each other based on the comparing, determine that the CPU box or the communication device of the internal device has been replaced, and obtain the management data of the device stored in association with the unique identification information of the internal device side from the non-volatile storage medium of the management computer. - communicate with the communication device of the internal device, - obtain the unique identification information of the internal device side, - compare the unique identification information of the internal device side with the storage data of the unique identification information of the internal device side read from the non-volatile storage medium of the CPU box, and, - if both do not match each other based on the comparing, determine that the CPU box or the communication device of the internal device has been replaced, and obtain the management data of the device stored in association with the unique identification information of the internal device side from the non-volatile storage medium of the management computer.