Korean medicated diet (KMD) is not a simple combination of food and Chinese drugs, but a special carefully constructed diet made from Sasang constitutional medicines, food and condiments under the theoretical guidance of diet preparation based on differentiation of symptoms and signs of traditional Sasang medicine (TSM). It combines the functional efficacy of medicine with the delicacy of food, and can be used to prevent and cure diseases, build up one's health and prolong one's life. Korean traditional medicated diet has a long history of development. Although influenced by Chinese medicine, Korean traditional medicine has been developed into a unique system of traditional medicine that has surpassed the continental medical practice, sublimating itself into a native medical practice suitable to Korean lifestyles and physical constitutions. In the 19th century, Lee Jema's Sasang medicine (medicine of four types of energy determining the physical constitution) was introduced. It is an integration of mind and body according to the individual's physical constitution that is categorized allowing a customized method of treatment ideal for each category-making the content of Korean traditional medicated diet even richer. The characteristics of Korean medicated diet are as follows: (1) Laying stress on the wole, selecting medicated diet on the basis of differential diagnosis. (2) Suitable for prevention and treatment, outstanding in effect. (3) Good in taste, convenient for taking. KMD refers to drink and food according to certain prescriptions, by processing and cooking that can be used either for prevention and cure of diseases, or for health care and recovery. The purpose of this review is to introduce TSM and KMD based on Sasang constitutional medicines.