During the Ming-Ch’ing period，the countries of maritime East Asia were in frequent economic and cultural contact with each other. In these contacts，Chinese characters were an important medium for facilitating exchange between China and its East Asian neighbors. In the course of this long-term exchange，each of the neighbor countries produced a considerable number of works written in Chinese，and they constitute an important basis for enabling us to examine East Asia as a single interconnected spatial unit. In recent years，large numbers of these overseas Chinese works have been published，and in particular Ryukyuan Chinese works have been attracting increasingly the atttention. Many publications have provided a considerable amount of new materials for the study of Ming-Ch’ing history. Apart from materials on political and economic history，which had already attracted，they also include historical texts reflecting the life in East Asian society. Not only are these materials pertain to the history of cultural exchange between China and Ryukyu，but they also provide valuable materials for the study of Chinese social history.