An electronic device is provided. The electronic device includes a communication device for transmitting or receiving a signal, a memory, and a processor connected to the communication device and the memory. The memory may store instructions for controlling the communication device so as to cause the processor to generate a key pair including a public key and a private key, receive authentication information from an authentication server by using the communication device, generate signature data by electronically signing the authentication information on the basis of the private key, generate transaction data including the signature data, transmit the transaction data to a blockchain network, and transmit transaction identification information corresponding to the transaction data to the authentication server.