"Biologically active supplement is natural health care food with no harm to the human body, rich in various vitamins and prevent us from disease. Aim of medicine is prevent from disease, treatment, diagnosis and to be clear such as indications, use, dose, main active substance, regulation of physiology. In This article, related knowledge of medicine and health care food, to clarify the relationship between health care food and medicine, which provide evidence for how to use health care food and medicine correctly. Biologically active supplements have many effects such as protects human body, improve health, prevent from disease etc, but the effects nature is not same. So biologically active supplements are not used as substitute to medicine. Key words: Biologically active supplement; medicine; difference."