Despite the large amount of educational literature, the material on the physiology of the kidneys in the framework of the curriculum for the course of normal physiology is difficult to perceive. The authors of the manual hope that their work will help to understand the most difficult issues of this topic. The manual provides modern ideas about the mechanisms of glomerular filtration, reabsorption and secretion, as well as some of the methods for assessing the functional state of the kidneys. In separate sections of the manual, issues related to the participation of the kidneys in the regulation of blood pressure, the body's water-salt balance, and acid-base balance are considered. The manual was written to help students of medical universities, but it will also be useful to practitioners.The authors thank Yuri Rakov, a 6th-year student of the medical faculty of the St. Petersburg State Medical University. acad. I. P. Pavlova for technical assistance in the preparation and design of the manual.