This disclosure relates to personal information management. Various embodiments disclosed herein relate to a personal information management device, a personal information management system, a personal information management method, and a computer-readable non-transitory medium that records the personal information. In an example, a personal information management method based on a blockchain or by using a smart contract based on a blockchain is provided. In another example, a portable electronic device and a system operating to manage personal information are provided. In another example, a computer-readable non-volatile recording medium having a computer code recorded therein, required for the personal information management, is provided.