A user information management device of a shared network, comprising: an acquiring unit, configured to acquire user management information from a user access management device, wherein the user management information comprises identification information of a participant operator and one of invalid user information and valid user information, the invalid user information is used to indicate a user equipment that has been detached from a network of the participant operator but a user context of the user equipment is still retained in the user access management device, and the valid user information is used to indicate a user equipment attached to the network of the participant operator; and an updating unit, configured to update access user information of the participant operator according to the user management information; wherein the acquiring unit comprises a first receiving subunit, a first determining subunit, and a first sending subunit, wherein the first receiving subunit is configured to receive an authentication request that is initiated by the user access management device according to an access request sent by a user equipment, wherein the authentication request carries the identification information of the participant operator; the first determining subunit is configured to: determine, according to the identification information of the participant operator, the participant operator to which the user equipment belongs, and determine a quantity of access users of the participant operator; the first sending subunit is configured to: when it is determined that the quantity of the access users exceeds a preset threshold, send a notification to the user access management device that carries a service of the participant operator, wherein the notification instructs the user access management device to report the user management information; and the first receiving subunit is further configured to receive the user management information sent by the user access management device. an acquiring unit, configured to acquire user management information from a user access management device, wherein the user management information comprises identification information of a participant operator and one of invalid user information and valid user information, the invalid user information is used to indicate a user equipment that has been detached from a network of the participant operator but a user context of the user equipment is still retained in the user access management device, and the valid user information is used to indicate a user equipment attached to the network of the participant operator; and an updating unit, configured to update access user information of the participant operator according to the user management information; wherein the acquiring unit comprises a first receiving subunit, a first determining subunit, and a first sending subunit, wherein the first receiving subunit is configured to receive an authentication request that is initiated by the user access management device according to an access request sent by a user equipment, wherein the authentication request carries the identification information of the participant operator; the first determining subunit is configured to: determine, according to the identification information of the participant operator, the participant operator to which the user equipment belongs, and determine a quantity of access users of the participant operator; the first sending subunit is configured to: when it is determined that the quantity of the access users exceeds a preset threshold, send a notification to the user access management device that carries a service of the participant operator, wherein the notification instructs the user access management device to report the user management information; and the first receiving subunit is further configured to receive the user management information sent by the user access management device.