"Sikui-simgam ("食醫心鑑", Book for Alimentotherapist)" written by Jameun, a doctor of Tang (唐) in the 9th century, propagated alimentotherapy in Korea, China, and Japan for a long time. In this study, Sikui-simgam medical theories were studied and the medicinal ingredients and types of food therapy were analyzed to understand alimentotherapy characteristics. "Sikui-simgam" is the first food therapy formulary diverged from herbal therapy forms. Various ingredients from "Sikui-simgam" show the food culture of the Tang age and report much about cooking and cultural history. Many prescriptions in the books are the origins of present-day food culture; thus, they are important clues to understand the present food culture. This book also describes actual prescriptions in detail. Various types of prescriptions with different ingredients are unique characteristics of food therapy and show the various possibilities for food therapy prescriptions. The food therapy prescriptions of "Sikui-simgam" were designed for medical specialists, as the book contains doses and incompatibilities for food therapy. Such food therapy prescriptions were used to treat diseases, so they were used with strict standards.