A visited network service using system, comprising a visited network and a home network, wherein the visited network comprises a first home subscriber server HSS and a servicing server connected to the first HSS, and the home network comprises a second HSS, characterized in that: the visited network further comprises a visiting virtual roaming management VVRM unit (1,10), adapted to log-in or log-out virtual terminal information after receiving a log-in or log-out notification of the virtual terminal information of a visiting terminal; and the VVRM unit is connected to the first HSS and/or the servicing server, and is adapted to log-in or log-out service subscription information after receiving a log-in or log-out notification of the service subscription information of a virtual terminal; the home network further comprises a home virtual roaming management HVRM unit, connected to the second HSS; and adapted to send a log-in notification of the virtual terminal information to the VVRM unit in the visited network according to a visited network service use license of a home terminal when detecting a registration message of the home terminal in the visited network and detecting that the virtual terminal information of the home terminal in the visited network is not activated, and send a log-in notification of the service subscription information to the VVRM unit in the visited network according to the visited network service use license of the home terminal when detecting that the virtual terminal information of the home terminal in the visited network is activated and requested service subscription information is not activated; and the VVRM unit and the HVRM unit are connected to each other, and are adapted to cooperate with each other to control a log-in or logout operation of the virtual terminal information and the service subscription information; wherein the virtual terminal information is the information of the virtual terminal which is adapted to be activated by the visited network for the visiting terminal, and to be used by the visiting terminal to activate services provided by the visited network. the visited network further comprises a visiting virtual roaming management VVRM unit (1,10), adapted to log-in or log-out virtual terminal information after receiving a log-in or log-out notification of the virtual terminal information of a visiting terminal; and the VVRM unit is connected to the first HSS and/or the servicing server, and is adapted to log-in or log-out service subscription information after receiving a log-in or log-out notification of the service subscription information of a virtual terminal; the home network further comprises a home virtual roaming management HVRM unit, connected to the second HSS; and adapted to send a log-in notification of the virtual terminal information to the VVRM unit in the visited network according to a visited network service use license of a home terminal when detecting a registration message of the home terminal in the visited network and detecting that the virtual terminal information of the home terminal in the visited network is not activated, and send a log-in notification of the service subscription information to the VVRM unit in the visited network according to the visited network service use license of the home terminal when detecting that the virtual terminal information of the home terminal in the visited network is activated and requested service subscription information is not activated; and the VVRM unit and the HVRM unit are connected to each other, and are adapted to cooperate with each other to control a log-in or logout operation of the virtual terminal information and the service subscription information; wherein the virtual terminal information is the information of the virtual terminal which is adapted to be activated by the visited network for the visiting terminal, and to be used by the visiting terminal to activate services provided by the visited network.