There must be a number of essential elements in performing translation and interpretation successfully. And among the many elements we can consider, the language ability, specially the mother tongue ability, should be at the top of these as a prerequisite for translation and interpretation. This study tries to observe the actual situation of the Korean language classes in the four major GSITs of Korea focusing on the class formation, the professors in charge, and the contents of the classes, and makes suggestions such as setting the proper standards of Korean language ability for translators and interpreters and opening the Korean language class for those who study Korean as a B language. This study also suggests the cooperation among the professional interpreters/ translators and the Korean language scholars as professors of the Korean language classes in GSITs, and development of proper curriculums and textbooks.