Background & Aim: Development of complementary medicine in the world, requires a detailed understanding of the fundamentals, principles and correct application by medical practitioners is inevitable. This study aimed to complete the review of the natural things in foundations of traditional medicine.
 Material and Methods: This review study aims to collect an overview of theoretical principles of Iranian Traditional Medicine (Tbyyh Affairs) and the relevant texts from the Internet (Google, SID.ir, MEDLINE, Magiran, Iranmeddex) with the keywords; natural things, foundations, Iranian traditional medicine. 30 articles were found 15 of which were
completely related published articles and original references in Iranian traditional medicine.                                                                                                      
Results: Theories and concepts of prevention, detection, recovery and treatment of diseases in traditional medicine are based on the holistic approach to patients. Disorders in traditional medicine in the areas of physical, emotional, mental, spiritual and environment are treated simultaneously. In this study, the definition of medicine from the perspective of Iranian scientists, the characteristics of traditional medicine, traditional medicine theory and concepts, definitions of health and illness, and the factors affecting them from the view point of ancient Iranian physicians and issues that medicine considers are provided.
 Conclusion: Holism -oriented philosophy of traditional medicine is a key element in all cases. So studying the literature traditional medicine (both herbal medicine and treatments based on traditional methods) theories and concepts and the use any kind of traditional medicine and cultural background is must be considered.