Ogyū Sorai (1666-1728) was one of the most influential Confucians of the Tokugawa period. His criticisms of Song Neo-Confucianism and his reinterpretations of the Confucian classics led him to formulate an innovative Confucian theory, which has been considered modern before its time. The Confucian theory of Ogyū Sorai was created not just in connection to his criticisms of Song Neo-Confucianism, but also in relation to his criticisms of "Kundoku (訓讀)" and his translation theory more generally. In fact, this problem has been well-researched. Most research on this topic, though, discusses it through modern linguistics or postmodern theories of language. In this paper, however, I attempt to examine his criticisms of "Kundoku" and his translation theory in the context of the "Kanbun learning (漢文學)" history of East Asia. I take this approach because his translation theory deals not just with the spoken languages of China and Japan, but also concerns the writing and learning of "Kanbun" in pre-modern Japan. I will survey the history of "Kundoku" and "Kanbun learning" in Japan, and then explain why Sorai criticized "Kundoku," and what translation theories he proposed to use in place of "Kundoku." In doing so, I will discuss the significance of Sorai's translation theory in East Asian intellectual history.