History textbooks of South Korea and Japan have been blamed for creating acute tension between the two countries. As social studies educators and researchers, instead of reacting emotionally to this situation, we need to examine what is different between the textbooks and think about how we can solve this problem from the perspective of education. This article compares and analyzes how the history textbooks of South Korea and Japan deal with Korean-Japanese history and considers how we can utilize the “difference” between them. With critical discourse analysis as a research method, we scrutinized the history textbooks of the two countries with the two standards: (1) selection and exclusion in terms of one’s own country’s history, and (2) discourse and sociocultural background that is beyond the descriptions of the textbooks. Firstly, we divided the Korean-Japanese history into four periods: 1) the emergence of Japan in the history textbook of South Korea to the period of the Three States, 2) the Unified Silla period, Goryeo period, and to the mid-Joseon period (before and after the Japanese Invasion of Korea in 1592 and in 1597), 3) the late-Joseon period to the Japan-Korea Annexation Treaty, and 4) Japan’s colonial rule to the present. Then, focusing on the value of communication, which is a methodology to utilize the “difference,” we suggest “intrapersonal communication” and “authentic communication” for making a social studies lesson open to another nation’s discourse and promoting South Korean and Japanese students’ mutual understandings.