Abstract: The system for issuing electronic documents using a blockchain according to the present invention comprises: a transceiver receiving identification information of a facility and status information of the facility from a complex sensor device for sensing the status of the facility and transmitting sensing the status of facilities and transmitting the status information of the facility to the outside; a diagnosis unit performing safety diagnosis on the facility and calculating a safety diagnosis grade according to the safety diagnosis result; a transmitter retrieving the safety diagnosis result from the distributed ledger of the blockchain network at the request of a user device and transmitting the safety diagnosis result in the form of an electronic document; and a data processer for converting the received status information of the facility and the safety diagnosis result by the diagnosis unit into a standardized data format suitable for storage in a blockchain network.