Virtual network adopting roaming access way based on mobile communication

The invention discloses a virtual network adopting a roaming access way based on mobile communication. The virtual network comprises mobile phone networks (1) and an authentication and accounting system (2) for authenticating the identities of user mobile phones (3), wherein the mobile phones (3) are provided with SIM cards belonging to the virtual network identity; the mobile phone networks (1) provide roaming access for mobile phones (3) of the virtual network, and perform authentication on accessed mobile phones (3) through the authentication and accounting system (2); and the authentication and accounting system (2) records the call volumes and data usage of the mobile phones (3) in the mobile phone network (1) through the mobile phone network (1), and charge the users according to thecall volumes and data usage. Through adoption of the virtual network, the service coverage can be expanded through access to different networks in a roaming way; the cost on repeated laying of base stations is lowered greatly through sharing of the base stations; and up to two thirds of base stations can be saved.