<b><i>Background:</i></b> Raman tweezers spectroscopy (RTS) is a powerful tool that combines optical tweezers and Raman spectroscopy to study single living cells. RTS has become increasingly popular in biomedical and clinical research due to its high molecular specificity and sensitivity, which enable the study of cell viability, cell deformation, cell-protein, cell-nanoparticle, cell-cell interaction, etc. In transfusion medicine, RTS can give valuable insights into the storage lesions and effects of various preservatives and intravenous fluids on blood cells. <b><i>Summary:</i></b> By analyzing the Raman spectra of individual blood cells, RTS can detect changes in the cellular blood components which can be used to monitor the quality of blood products during storage and transfusion. The present review article highlights the principle and clinical applications of RTS in transfusion medicine. <b><i>Key Messages:</i></b> Raman spectroscopy is a versatile analytical method for biomedical research. Combining the Raman spectroscopy method with the optical tweezers technique will allow us to explore the dynamics of live single cells in their physiological medium.