This study is to clarify that there has been existed the ‘Korea Language School’ that replaced ‘The Language School’, the educational institution for the Christian Missionaries in Korea before Korea was liberated from Japan's colonial rule. This is a part of the research that focuses on the formation of the modern Korean language education until the Korean Language Institute at Yonsei University, the first modern Korean Language Institute, was established in Seoul, Korea. As a result, this study found that the ‘Korea Language School' has existed from the year of 1949 to 1958, which had never been reported before, and also examined the purpose, the participants, the contents and the curriculum of education, showing some problems the language school had at the time which eventually brought the establishment of the Korean Language Institute at Yonsei university as a solution to those problems. Therefore, it is concluded that the modern Korean Language Education, started from the establishment of Yonsei Korean Language Institute, was originated from the Korean Language Education for the Christian Missionaries. In addition, this study clarified the process of formation of modern Korean language education to some extent, despite that it remains some extra works to review the curriculum and the textbooks used in the beginning of Yonsei Korean Language Institute more closely. (The University of Shimane)