A method and system for implementing L3VPN based on a two-dimensional routing protocol. The method includes the following steps of: activating an L3VPN network to obtain a route destined to each user site; sending, by a user in a source user site, a packet to a user in a target user site, and sending the packet to an entry of a first edge routing device; performing encapsulation by the first edge routing device based on a public network IP address of the packet; and forwarding, by means of matching of two-dimensional routing, the encapsulated packet to an exit of the first edge routing device for decapsulation, and forwarding the same to the target user site via an entry of a second edge routing device.