The present invention discloses a protocol interworking device between an application server and a terminal and a method for implementing the same. The method comprises: a domain name resolution module that comprises a domain name information record library and a domain name dynamic record processing sub-module and is used for receiving records of a domain name from a dynamic domain name server and querying other records of the domain name from a protocol conversion module; and the protocol conversion module that comprises an earthquake mapping relation record library and a mapping relation processing sub-module and is used for generating record information of the domain name through querying an address mapping relation record library or selecting an IP address from an address database and returning a result to the domain name resolution module. The protocol interworking device and the method are able to associate the records about the online and dynamic domain name establishment of the application server with the process for the protocol conversion module to establish an address mapping relation, to change the implementation process for triggering and establishing an address mapping relation via a terminal access, to improve the domain name resolution process for different protocol stack interworking scenes, and to optimize the process for the domain name resolution module and the protocol conversion module to establish an address mapping relation.