A roaming charging method performed by a home charging device, the method comprising the steps of: • receiving (S 209), from a blockchain network, a roaming account balance, a roaming charging rule, and a roaming service statistics abstract that are for a user, wherein the roaming service statistics abstract is acquired by performing a hash operation on roaming statistics for the user obtained by a visited service statistics collection device; receiving (S 210) roaming service statistics for the user from a service statistics database; • verifying (S 211) that an abstract obtained based on the received roaming service statistics for the user is the same as the received roaming service statistics abstract, by using a digital signature algorithm; and • verifying (S 212), based on the received roaming service statistics and the received roaming charging rule, correctness of the received roaming account balance, wherein the home charging device enters the roaming charging rules and the roaming service statistics into a charging engine to obtain a roaming fee, and to obtain a balance based on the roaming fee and a home account balance, and compares the balance with the blockchain network, wherein before the reception of the roaming account balance, the roaming charging rule, and the roaming service statistics abstract that are for the user from the blockchain network, the method further comprises: sending a request message to the blockchain network, wherein the request message carries a user identifier of the user and a channel identifier, and the request message is used to request the roaming account balance, the roaming charging rule, and the roaming service statistics abstract that are for the user from a channel indicated by the channel identifier, and wherein before the sending the request message to the blockchain network, the method further comprises: • determining an initial roaming account balance for the user based on a home account balance for the user; and • sending, to the blockchain network, the initial roaming account balance for the user and the channel identifier corresponding to the user, wherein a plurality of peer nodes on the channel indicated by the channel identifier store one or more of the initial roaming account balance, the roaming charging rule, and the roaming service statistics abstract in a form of a blockchain. • receiving (S 209), from a blockchain network, a roaming account balance, a roaming charging rule, and a roaming service statistics abstract that are for a user, wherein the roaming service statistics abstract is acquired by performing a hash operation on roaming statistics for the user obtained by a visited service statistics collection device; receiving (S 210) roaming service statistics for the user from a service statistics database; • verifying (S 211) that an abstract obtained based on the received roaming service statistics for the user is the same as the received roaming service statistics abstract, by using a digital signature algorithm; and • verifying (S 212), based on the received roaming service statistics and the received roaming charging rule, correctness of the received roaming account balance, wherein the home charging device enters the roaming charging rules and the roaming service statistics into a charging engine to obtain a roaming fee, and to obtain a balance based on the roaming fee and a home account balance, and compares the balance with the blockchain network, wherein before the reception of the roaming account balance, the roaming charging rule, and the roaming service statistics abstract that are for the user from the blockchain network, the method further comprises: sending a request message to the blockchain network, wherein the request message carries a user identifier of the user and a channel identifier, and the request message is used to request the roaming account balance, the roaming charging rule, and the roaming service statistics abstract that are for the user from a channel indicated by the channel identifier, and wherein before the sending the request message to the blockchain network, the method further comprises: • determining an initial roaming account balance for the user based on a home account balance for the user; and • sending, to the blockchain network, the initial roaming account balance for the user and the channel identifier corresponding to the user, wherein a plurality of peer nodes on the channel indicated by the channel identifier store one or more of the initial roaming account balance, the roaming charging rule, and the roaming service statistics abstract in a form of a blockchain. • determining an initial roaming account balance for the user based on a home account balance for the user; and • sending, to the blockchain network, the initial roaming account balance for the user and the channel identifier corresponding to the user, wherein a plurality of peer nodes on the channel indicated by the channel identifier store one or more of the initial roaming account balance, the roaming charging rule, and the roaming service statistics abstract in a form of a blockchain.