A method for implementing network intercommunication, wherein a communication end of a Locator/ID Separation Protocol, LISP, network intercommunicates with a communication end of an Internet through a LISP data packet conversion device and an intercommunication data packet conversion device, a LISP communication end is located in a LISP network, and has an endpoint identity for indicating identity, a router locator for indicating location, and an IP address for realizing intercommunication; the Internet communication end is located in an Internet and has an IP address, an endpoint identity for indicating identity and realizing intercommunication, and a router locator for indicating location, and the method comprises: a step of transmitting a LISP single-layer data packet, wherein the LISP single-layer data packet is transmitted between the LISP communication end and the LISP data packet conversion device, and a source address and a destination address of the LISP single-layer data packet are represented by endpoint identities; a step of converting a LISP data packet, wherein the LISP data packet conversion device implements inter-conversion between a LISP single-layer data packet and a LISP double-layer data packet, outer source address and destination address of the LISP double-layer data packet are represented by router locators, and inner source address and destination address are represented by endpoint identities; a step of transmitting the LISP double-layer data packet, wherein the LISP double-layer data packet is transmitted between the LISP data packet conversion device and an intercommunication data packet conversion device; a step of converting an intercommunication data packet, wherein the intercommunication data packet conversion device implements inter-conversion between a LISP double-layer data packet and an IP data packet, and a source address and a destination address of the IP data packet are represented by IP addresses; and a step of transmitting an IP data packet, wherein the IP data packet is transmitted between the intercommunication data packet conversion device and the Internet communication end; thereby realizing intercommunication between a location/identity separation network and the Internet; wherein the endpoint identity, router locator and IP address of the Internet communication end are the same. a step of transmitting a LISP single-layer data packet, wherein the LISP single-layer data packet is transmitted between the LISP communication end and the LISP data packet conversion device, and a source address and a destination address of the LISP single-layer data packet are represented by endpoint identities; a step of converting a LISP data packet, wherein the LISP data packet conversion device implements inter-conversion between a LISP single-layer data packet and a LISP double-layer data packet, outer source address and destination address of the LISP double-layer data packet are represented by router locators, and inner source address and destination address are represented by endpoint identities; a step of transmitting the LISP double-layer data packet, wherein the LISP double-layer data packet is transmitted between the LISP data packet conversion device and an intercommunication data packet conversion device; a step of converting an intercommunication data packet, wherein the intercommunication data packet conversion device implements inter-conversion between a LISP double-layer data packet and an IP data packet, and a source address and a destination address of the IP data packet are represented by IP addresses; and a step of transmitting an IP data packet, wherein the IP data packet is transmitted between the intercommunication data packet conversion device and the Internet communication end; thereby realizing intercommunication between a location/identity separation network and the Internet; wherein the endpoint identity, router locator and IP address of the Internet communication end are the same.