The invention discloses a network access method and a network access system. The network access method comprises the following steps: performing identity authentication on a network terminal based on a Radius protocol through an operator network BNG (broadband network gateway) and an AAA (authentication authorization accounting) server; in response to passing of the identity authentication, sending an identity authentication passing message for the network terminal to an access management unit of a cloud computing platform by the AAA server, so that when the network terminal logs in a virtual dual-stack host system of the cloud computing platform, the access management unit of the cloud computing platform can directly identify the network terminal according to the identity authentication passing message sent by the AAA server, and allows the network terminal to log in the virtual dual-stack host system. According to the technical scheme provided by the invention, secondary authentication on the network terminal caused by isolation between the BNG equipment of a network layer and the cloud computing platform of an application layer is avoided, the authentication flow of a user is simplified, and meanwhile, the user can conveniently access the internet through the virtual dual-stack host system provided by the cloud computing platform.