The physical properties (mechanical and electrical properties) of RBCs have been intensively studied over the last decade because of their physiological and pathological importance. It is well known that the exceptional deformability of RBCs is closely related to both the macrocirculation and the microcirculation. Impaired deformability of RBCs leads to a variety of diseases such as sepsis, malaria, sickle cell anemia (hemoglobin disorder), and microvascular dysfunction. In addition, the electrical properties of RBCs are also associated with pathological conditions. Advances in biophysical measurements have made it possible to use label-free, less invasive methods to characterize RBCs and to study unknown structure-function relationships. A number of techniques have been used to measure the biophysical properties of RBCs, such as atomic force microscopy and optical tweezers. However, these techniques are difficult to use and the speed of testing is low. Currently, the application of modern spectroscopic, microscopic and microfluidic techniques to biomedical analysis is opening up new horizons and providing new perspectives in the study of RBCs and the pathology of RBC-related diseases.