Digital identity authentication method and system based on block chain

The invention discloses a digital identity authentication method and system based on a block chain, and belongs to the technical field of block chains. The method comprises the steps that an authentication terminal sends a credential request to a user terminal, the credential request carries a credential template identifier of a credential template, and the credential template is issued on a block chain by a certificate issuing mechanism; the user terminal obtains a DID identifier of a user according to a credential template corresponding to the credential template identifier, obtains m user certificates according to the DID identifier, generates credentials and credential proof according to the m user certificates and the credential template, and sends the credentials and the credential proof to the authentication terminal, the user certificates are issued to the user by a certificate issuing mechanism through a block chain, and m is greater than or equal to 1; and the authentication terminal verifies the cr