Currently, the parathyroid glands (PG) are admited as vital organs in humans. At the same time, the way to this acknowledgment was long and difficult, and the establishment of a link between the pathological conditions of the PG and their complications passed through many mistakes and errors. Understanding the regulation of calcium-phosphorus metabolism in the body and recognition of the main role of parathyroid hormone (PTH) in it was slow, throughout the XIX − early XX centuries. Despite the increasing number of observations confirming the development of complications because of hyperfunction of the PG or development of tetany due to their removal, the main link of this relationship remained unidentified for a long time. In view of the unique anatomical features of the PG, they were the last of the endocrine glands found, which the main obstacle was in the rapid study of their functional characteristics. Today, the structure and functions of the PG are described in detail, the manifestations of their various pathological conditions are well studied, and the capabilities of modern medicine allow timely diagnosis and treatment of diseases. The review describes the history of the discovery of the PG, highlights the main stages in the study of their role in calcium-phosphorus metabolism in particular and in the body as a whole, and discusses the prospects for further development in this direction. We analyzed the work devoted to the evolution in the notions of anatomical, physiological, pathological features of the PG.