A method, apparatus and system for virtual network configuration and partition handover are provided. The virtual network configuration method includes the following steps: The serving edge device obtains a target virtual network identifier and a corresponding interface identifier, uses the target virtual network identifier and the corresponding interface identifier to generate a Layer-2 Control (L2C) protocol packet, and sends out the L2C protocol packet; the communication proxy device that receives the L2C protocol packet obtains the target virtual network identifier and the corresponding interface identifier from the L2C protocol packet, and sets up a mapping relation between a target virtual network and an interface.