An authentication method and system oriented to a heterogeneous network are disclosed. After receiving a service request sent by a virtual terminal, a unified authentication platform generates a service token according to the service request, and sends the service token to the virtual terminal and a target network; the virtual terminal submits the service token to the target network, and requests the target network to provide service data; and the target network compares the service token submitted by the virtual terminal with the service token sent to the target network by the unified authentication platform, and provides the service data to the virtual terminal when the service token submitted by the virtual terminal is consistent with the service token sent to the target network by the unified authentication platform. By a unified authentication platform, the disclosure unifies authentication systems in a ubiquitous network, reduces huge signaling overhead and service delay in a heterogeneous network due to authentication, and improves authentication efficiency in the ubiquitous network.