An identification code management method and management system includes that the issue and distribution of an ID code having a message authentication code are managed thereby to efficiently and reliably manage a material object using the ID code. An electronic circuit chip with an ID code having a message authentication code stored in a read-only area is used as an identification tag. The information at an ID code order receiving terminal and an identification tag production factory terminal are consolidated and collectively managed at an ID code management terminal. Thereby, the ID code management terminal is inquired of highly confidential information or requested to process the information as required so that an ID code utilization terminal is not required to store the same information.