Objectives: The purpose of this study is to clearly understand the emotion theory in the Canon of Internal Medicine and correctly apprehend the concept of chiljeong. Methods: To perform a comparative study on the emotion theory between the Canon of Internal and recent studies published at papers and specialty publications for emotion within oriental medicine. Results: A number of advanced opinions on the relationships between chiljeong, five emotions and ohsin were obtained. Conclusions: Chiljeong is the most fundamental theory in the psychology of oriental medicine, and therefore, deserves a thorough and enthusiastic study.