Nanomaterial-based sensors have widely been utilized as promising platforms in multidisciplinary areas such as scientific, technology, biomedical, materials science, and engineering fields for detection applications. Among them, functionalized magnetic nanoparticles containing both inorganic and organic components are unique as a cost-effective and simple detection method because of the low detection limits, wide linearity, high sensitivity, reliable and rapid response, etc. Recent years witnessed that point-of-care systems exhibited a significant role in the diagnostics of different diseases since point-of-care sensors allow rapid detection of analytes in diagnosis, monitoring, and management of diseases. This chapter focuses on the preparation of functionalized magnetic nanoparticle-based sensors and highlights their point-of-care applications. Herein, we demonstrate the versatility and advantages of using functionalized magnetic particles with different analyte types and measurement method approaches over the past 3 to 5 years. Lastly, we believe that this chapter will provide valuable information and perspective for interested researchers.