The interpreter in the Qing Dynasty has played a key role in the development of overseas trade，whose formation and evolution has exerted extremely important influence on its diplomacy and foreign trade，even the sino-foreign cultural exchanges.Through research focusing on the types，sources and functional evolution of the interpreters who engaged in overseas trade，this article means to arouse the academic interest，thus attract more attention in the investigation of this group，hoping to provide an objective and accurate evaluation of the interpreters’ role in the history of China’s foreign relations.