A computer-implemented method for blockchain address mapping, to be performed by a system for blockchain address mapping, comprising: obtaining, from a client, one or more local accounts, one or more identifications of one or more blockchains, and one or more requests for creating in the one or more blockchains a plurality of blockchain addresses in association with the one or more local accounts, wherein the client corresponds to the one or more local accounts in the system; generating a plurality of public-private key pairs respectively for the plurality of blockchain addresses to be created, comprising: in a Trusted Execution Environment, TEE, and for each of the plurality of blockchain addresses, generating a public-private key pair and encrypting a private key of the public-private key pair; creating the plurality of blockchain addresses respectively in the one or more blockchains in association with the one or more local accounts and a plurality of public keys of the plurality of public-private key pairs, comprising, for each of the plurality of blockchain addresses, storing the encrypted private key in a Key Management System, KMS; storing, in a database, a plurality of mapping relationships among the one or more local accounts, the plurality of created blockchain addresses, the plurality of public-private key pairs, and the one or more identifications of the one or more blockchains, comprising: for each of the plurality of blockchain addresses, storing a mapping relationship among one of the one or more local accounts, the each of the plurality of blockchain addresses, a corresponding KMS directory, and one of the one or more identifications of the one or more blockchains, wherein the KMS directory links to the corresponding encrypted private key, wherein the TEE is configured to decrypt the corresponding encrypted private key; and transmitting a notification to the client for the client to correspondingly store the one or more local accounts in association with the one or more identifications of the one or more blockchains, wherein: the notification comprises the one or more local accounts for which the plurality of blockchain addresses are created and the one or more corresponding identifications of the one or more blockchains, and the plurality of blockchain addresses and the plurality of private keys of the plurality of public-private key pairs are stored in the system and are not stored at the client. obtaining, from a client, one or more local accounts, one or more identifications of one or more blockchains, and one or more requests for creating in the one or more blockchains a plurality of blockchain addresses in association with the one or more local accounts, wherein the client corresponds to the one or more local accounts in the system; generating a plurality of public-private key pairs respectively for the plurality of blockchain addresses to be created, comprising: in a Trusted Execution Environment, TEE, and for each of the plurality of blockchain addresses, generating a public-private key pair and encrypting a private key of the public-private key pair; creating the plurality of blockchain addresses respectively in the one or more blockchains in association with the one or more local accounts and a plurality of public keys of the plurality of public-private key pairs, comprising, for each of the plurality of blockchain addresses, storing the encrypted private key in a Key Management System, KMS; storing, in a database, a plurality of mapping relationships among the one or more local accounts, the plurality of created blockchain addresses, the plurality of public-private key pairs, and the one or more identifications of the one or more blockchains, comprising: for each of the plurality of blockchain addresses, storing a mapping relationship among one of the one or more local accounts, the each of the plurality of blockchain addresses, a corresponding KMS directory, and one of the one or more identifications of the one or more blockchains, wherein the KMS directory links to the corresponding encrypted private key, wherein the TEE is configured to decrypt the corresponding encrypted private key; and transmitting a notification to the client for the client to correspondingly store the one or more local accounts in association with the one or more identifications of the one or more blockchains, wherein: the notification comprises the one or more local accounts for which the plurality of blockchain addresses are created and the one or more corresponding identifications of the one or more blockchains, and the plurality of blockchain addresses and the plurality of private keys of the plurality of public-private key pairs are stored in the system and are not stored at the client. the notification comprises the one or more local accounts for which the plurality of blockchain addresses are created and the one or more corresponding identifications of the one or more blockchains, and the plurality of blockchain addresses and the plurality of private keys of the plurality of public-private key pairs are stored in the system and are not stored at the client.