Red blood cells (erythrocytes) are one of the most common cells in the human body and are responsible for transporting oxygen to tissues and removing carbon dioxide from the body. The study of the structure of erythrocyte membranes is of great importance for understanding their functions and the possibility of detecting various pathological conditions associated with a violation of the mechanical properties of membranes. Atomic force microscopy is a powerful tool for studying the nanostructural properties of membranes and allows the obtaining of high-quality images and data on mechanical properties. This article describes an experimental technique used to study the structure of erythrocyte membranes, as well as the results obtained and their analysis. The morphology and elastic properties of blood cells were analyzed by atomic force microscopy. Quantitative estimates of the elastic modulus of the cell membrane in the mode of force spectroscopy have been performed. The values of the elastic modulus of erythrocytes were determined depending on the localization of the indentation area and the time of exposure to the membrane surface by the probe. A significant dependence of the results of the elastic modulus estimation on the rate of indenter action on the cell membrane is shown.