Metal–organic frameworks (MOFs) are well-organized crystalline hybrids, constructed by coordination polymerization of organic ligands with transition metals. Recently, nanoscale MOFs have been thoroughly investigated as a very adaptable platform for functional applications across numerous domains due to their huge surface area, good biocompatibility, biodegradability, and hierarchically porous and customizable structure. Because so many different metallic and organic components can be employed to create nanoscale MOFs, they can act as the foundation for innovative biological materials and systems. Furthermore, the versatile functionalities such as porosity and oriented frameworks make them promising material in biomedical fields (drug and vaccine delivery, targeted therapy for cancer and infectious disease) and point-of-care diagnostics in which they can be used as a framework to immobilize biomolecules for the selective and targeted identification of biomarkers, such as antibodies or DNA probes. This book chapter provides an overview of the current nanoscale MOF-related research, emphasizing synthesis methodologies and the wide bio-applications of nanoscale MOFs, including drug delivery, sensing platforms, and anticancerous and antimicrobial agents. It also highlights areas of prospective future research in the field of nanoscale MOFs.