A charging policy obtaining method, wherein the method is used in a broadband network gateway, and comprises: receiving an authentication, authorization, and accounting request from user equipment, wherein the authentication, authorization, and accounting request comprises a user name and a user equipment identifier, wherein the user equipment identifier comprises one or more of a circuit identifier, circuit ID, of the user equipment and a media access control, MAC, address of the user equipment, wherein the circuit ID is used to identify circuit information of the user equipment; sending a charging policy request to a first server, wherein the charging policy request comprises a first field and a second field, the first field is used to carry the user name, and the second field is used to carry the user equipment identifier; and receiving a charging policy response sent by the first server, wherein the charging policy response comprises a charging policy corresponding to the user name and the user equipment identifier, and obtaining the charging policy from the charging policy response, wherein the authentication, authorization, and accounting request further comprises a password corresponding to the user name, and before sending the charging policy request to the first server, the method further comprises: sending an authentication and authorization request to a second server, wherein the authentication and authorization request comprises the user name and the password; and receiving an authentication and authorization response sent by the second server, wherein the authentication and authorization response comprises a result of authentication and authorization that are performed based on the user name and the password; and wherein sending the charging policy request to the first server further comprises: if the result of authentication and authorization indicates a success, sending the charging policy request to the first server; and if the result of authentication and authorization indicates a failure, sending no charging policy request to the first server. receiving an authentication, authorization, and accounting request from user equipment, wherein the authentication, authorization, and accounting request comprises a user name and a user equipment identifier, wherein the user equipment identifier comprises one or more of a circuit identifier, circuit ID, of the user equipment and a media access control, MAC, address of the user equipment, wherein the circuit ID is used to identify circuit information of the user equipment; sending a charging policy request to a first server, wherein the charging policy request comprises a first field and a second field, the first field is used to carry the user name, and the second field is used to carry the user equipment identifier; and receiving a charging policy response sent by the first server, wherein the charging policy response comprises a charging policy corresponding to the user name and the user equipment identifier, and obtaining the charging policy from the charging policy response, wherein the authentication, authorization, and accounting request further comprises a password corresponding to the user name, and before sending the charging policy request to the first server, the method further comprises: sending an authentication and authorization request to a second server, wherein the authentication and authorization request comprises the user name and the password; and receiving an authentication and authorization response sent by the second server, wherein the authentication and authorization response comprises a result of authentication and authorization that are performed based on the user name and the password; and wherein sending the charging policy request to the first server further comprises: if the result of authentication and authorization indicates a success, sending the charging policy request to the first server; and if the result of authentication and authorization indicates a failure, sending no charging policy request to the first server. sending an authentication and authorization request to a second server, wherein the authentication and authorization request comprises the user name and the password; and receiving an authentication and authorization response sent by the second server, wherein the authentication and authorization response comprises a result of authentication and authorization that are performed based on the user name and the password; and wherein sending the charging policy request to the first server further comprises: if the result of authentication and authorization indicates a success, sending the charging policy request to the first server; and if the result of authentication and authorization indicates a failure, sending no charging policy request to the first server. if the result of authentication and authorization indicates a success, sending the charging policy request to the first server; and if the result of authentication and authorization indicates a failure, sending no charging policy request to the first server.