Modern medicine can not solve all the problems caused by many intractable, chronic and aging related diseases hence more people have come to recognize the role of foods for the promotion of good health as well as prevention from illness. Further more, controlled diet are proven to be used as effective cures for certain diseases. In this paper, the definition, functional factors and mechanisms of designer(funtional) foods are reviewed. Especially, the biofuntional activities of herbal medicines which also can be treated as designer foods are intensively noted in this paper.