<p>Cell sorting is a crucial process in stem cell research, regenerative medicine, and cell engineering. It is typically performed in sterile environments using limited dilutions, density gradient centrifugation, membrane filtration, flow cytometry-assisted cell sorting (FACS) based on the detection of fluorophores, or magnetic-activated cell sorting (MACS) based on paramagnetic properties. MACS is a popular choice for cell sorting, known for its cost-effectiveness and independence from high-end equipment. Paramagnetic iron oxide nanoparticles (IONP) are the most commonly used nanomaterials for cell sorting owing to their strong paramagnetic properties, biocompatibility, cost-effectiveness, ease of synthesis, and availability. IONPs, with their wide range of biomedical applications, including cell transplantation, detection of circulating cancer cells, stem cell therapy, and regenerative medicine, inspire a new wave of research and development. This review will focus on the current state of research, fabrication methods, and applications of IONPs in cell sorting, with potential applications in the biomedical realm.</p> Graphical Abstract <p></p>