The invention relates to an identity authentication method, system and device based on a block chain, computer equipment and a storage medium. The method comprises the following steps: receiving a login request sent by a user terminal, the login request carrying private key signature data; responding to the login request, obtaining public key data; obtaining equipment identification data of the user terminal when verification of the private key signature data is completed according to the public key data, and generating key data according to the equipment identification data, and sending the key data to the user terminal, receiving authentication data submitted by the user terminal for the key data, and when the authentication data submitted by the user terminal passes the verification, determining that the identity authentication is passed. According to the scheme, decentration is carried out in a blockchain mode, so that authentication failure caused by downtime of the central node is avoided; by introducing a double-authentication mechanism of equipment authentication and key data based on equipment identification data and private key authentication, behaviors such as signaturedenial can be avoided, the identity authentication accuracy is improved, and the data security is guaranteed.