The aim of this study is a basic research to understand the overseas Koreans' social life environment, their mindset, present status of the use of language in daily life and factors in the present status, and to prepare a cornerstone of the education of the Korean language for overseas Koreans. The research contents are summed up as follows: In Chapter 1, this study examined the research purpose and significance, necessity of the research, and theoretical frame of the research background for overseas Korean people's language use in daily life. In Chapter 2, this study examined through what period background and what historical process the overseas Koreans have formed and how their present situation is going today through literature review. In addition, this study looked into the actual condition of their use of the Korean language and its education. In Chapter 3, this study, in an effort to understand the actual situation of overseas Koreans' language use in daily life, discussed the research methodology on how to select the research country and research district and which research method could make it possible to collect and analyzed accurate data, and also discussed the research items and data analysis method. In Chapter 4, as a preliminary study for grasping the actual condition of overseas Koreans' language use in daily life, this study conducted an interview survey and in-depth interview survey of the Korean residents who were living in Osaka and the surrounding area of Tokyo. This survey was carried out in order to understand the use of language according to the overseas Koreans' immigration time & generations, and the use of language according to a speech situation and a speech counterpart, etc. On the basis of the survey results, this study made an overall analysis of the actual condition of the language use, such as the determinant of the language choice of the new and old generation, and using aspects of the interlanguage with the aim of looking deeper into the universality and uniqueness of each district when this survey is expanded and developed into even the scope of the overseas Koreans's society in other districts by improving various problems in research methods revealed in the model survey. In Chapter 5, this study established the medium and long term survey plan to be carried out with focus on China, the Commonwealth of Independent States, the US, Brazil and Japan for the following 5 years [2012~2016]on the basis of the model survey experience and survey results in the actual circumstances of shortage in the preliminary data on the actual condition of the overseas Korean people's language use in daily life and their mindset. The data obtained from the medium and long term survey will be very useful preliminary data for the continuous study.