Korean language education in school system started in the 1890s as a part of modernization of Korea, and Korean textbook has been the symbol of linguistic democracy abolishing discrimination in literacy. But Korean textbook is temporarily due to the irregular amendment of curriculum and optional with teacher’s right to select teaching materials. In principle Korean textbook can be compiled by participator’s democratic agreement which is the base for selecting diverse texts from every sphere of the society. Korean textbook has been the text of Korean subject as well as the text of tool subject, now it is the time for Korean textbook to play a role in curriculum Integration. As the text of tool subject Korean textbook should be compiled to increase learner’s Korean competence corresponding to the intellectual level of other subjects. As the text of Korean subject Korean textbook should cover diverse linguistic materials on the criterion of the development of Korean and Korean culture. In addition to Korean textbook other teaching materials such as anthology should be used actively to broaden learner’s experience of text. As the teaching materials for curriculum Integration Korean textbook should maintain diversity of information, knowledge, genre, and quality level of text to communicate with other subjects. Especially for the trans-disciplinary integration authentic texts in the real social context should be introduced into class. And management system of teaching materials is necessary for teacher and student to select appropriate materials among textbook, anthology, and authentic texts in real world according to learning objective.