Red blood cell (RBC) parameters such as morphology, volume, refractive index, and hemoglobin content are of great importance for diagnostic purposes. Digital holographic microscopy (DHM) is a well-suited technique for studying RBCs since it is a perfect phase object. Also, DHM is a contactless and non-invasive method thus the sample can be studied again without damaging the sample. In this study, we show quantitative analysis of RBCs’ characteristic or clinical properties such as volume, membrane surface area, projected surface area, sphericity index, RBC’s radius, sphericity coefficient, and membrane fluctuation rate at the single cell level using DHM. These parameters will be helpful for RBC experts and hematologist.