The Sassanid Empire ruled in Iran between 224 AD and 651 AD. The founder of this dynasty, Ardashir I (241-224 AD), a Zoroastrian cleric, took two very important steps in the beginning; One was the creation of a central government and the other was the formalization of the religion of Zoroaster. The homogeneity and alignment of government and religion in the Sassanid administration had very important effects on the growth and development of science and knowledge, especially medical science, which began in the Achaemenid Empire (330 559 AD). The under-consideration question in this research is that despite the class system and the monopoly of learning science and knowledge in the privileged classes of society, what was the status of medical science in the Sassanid period? This study showed that medical science had the highest position in the teachings of Zoroastrian religion; Because with that, they took care of their health and performed their religious duties well, and with it, they overcame the devil. In Zoroastrian religious texts, the duties and characteristics of the physician, the types of diseases and how to treat and the rules related to ‘Tebabat’(medicine) are discussed. In addition to this, the encouragement policy of kings and Sassanid government, including; Expanding cultural and scientific relations with India, Greece and Rome, translating the works of foreign physicians into Pahlavi and archiving them along with the formation of a large library, inviting foreign physicians to work at ‘GondiShapur’ University and sending Iranian physicians abroad in order to acquire more medical knowledge and experience, they were very influential in the growth and development of medical science. The current study has been conducted in a historical method with reference to library sources and archaeological sources as well as new researches have been used to complete the topics. It seems that due to the spread of Iranian civilization in the Sassanid era and paying attention to science and knowledge as well as the creation of a medical city in the Sassanid period, medical knowledge had a great importance in this period and this knowledge was researching professionally.
