The invention relates to the technical field of cloud computing management, in particular to a method for distributed virtual networks applicable to a cloud platform. According to the method, any number of physical nodes are selected as network nodes of the cloud platform, and the network nodes establish and provide virtual network service; establishment of the network nodes includes the steps that (1), a virtual switch module is installed and started, and a virtual switch and an intranet network bridge are established; (2), an intranet network card is connected into the intranet network bridge; (3), the virtual switch and the intranet network bridge are connected, and a communication module for the node and other intranet nodes is set; (4), local VLAN ports are added; (5), the multiple virtual networks are established; (6), a virtual route is established; (7), an extranet network bridge is established, and an extranet network card is connected in; (8), a virtual route is established. Single-point failures of centralized network service of the cloud platform can be avoided, load balance of the network service nodes is achieved, the virtual networks can be managed flexibly and conveniently, and the method can be used for realizing the distributed virtual networks.