In recent years, transnationalism (supranationalism) humanities has been paid attention in the field of East Asian discourse, which goes beyond the boundaries of regional, national, and geographical areas to study and studies history, philosophy, literature, society, culture, and political phenomena. Transnationalism seeks to look at various phenomena from a more objective viewpoint, not from the perspective of any particular nation state. This paper starts from this context and examines narrowly not only aspects of Korean modern thought but broadly East Asian modern history. In other words, this article attempts to identify a perspective that transcends the border between the nation and ethnic group in modern history of East Asia. When we can find it, the actual image of East Asian modern history will be rediscovered. Thus, this essay was designed to explore the possibilities of nationalism and transnationalism in Korean modernism from the viewpoint of modern history of East Asia, that is, the ideological historical viewpoint of the East Asian Three Countries (Korea, China, and Japan). In this regard, this paper analyzes the supernationalist discourses and ideas of Korean modern intellectuals, and intellectuals of East Asian modern intellectuals (especially China and Japan). For this discussion, this essay compares probes the modern thought of China and Japan - the theory of Chinese harmony, and the theory of middle classes - a comparative study with modern thought of Korea. Since the mid-1980s, cross-border globalization has been sweeping everywhere and is continuing today. Transnationalism is a synonym for globalization, and the transnational phenomenon is constantly maintained in all areas of the world. The scholarship of modern Asia in East Asia was also a signal to announce the prelude of Transnational Thoughts. It was the ideological arena of East Asian modernity that coexisted with the transnationalist thinking that tried to compromise and harmonize with the aggressive acceptance and of nationalistic thought against the tendency which crossed the border.