Abstract
This article widely covers the path of medical research of the Iranian scientist-encyclopedist, physician, philosopher, chemist Abu Bakr Muhammad al-Razi, who lived in 850-923, and his contribution to the development of medicine. His works on medicine describe in great detail and in an accessible form the methods of diagnosing and treating patients. The medical views of Abu Bakr Muhammad al-Razi on the etiology and pathogenesis of diseases were close to modern ones.