The textbook is written in accordance with the curriculum of the course "Normal Physiology" and reflects many years of experience in teaching the subject at the departments of normal physiology of RNIMU . N. and . Pirogov and RUDN . In addition to the chapters covering the physiology of individual organs and systems, the textbook includes the chapters “Cell Physiology”, “Characteristics of Regulatory Mechanisms”, “General Physiology of Excitable Tissues”, as well as “Human Ecology and the Foundations of Valeology” and “Physiology of Labor Activity” .. Particular attention is paid to discussion issues, including the problems of cell interaction with the help of electric fields. Strong assimilation of material is facilitated by illustrations and tables. The first two editions of the textbook were a great success for students and teachers of medical universities. The third edition has been substantially refined in light of modern advances in physiology. For students of various faculties of medical and biological universities .