MXenes have potential applications in biomedicine, ranging from sensors and cancer theranostics to targeted drug delivery and tissue engineering/regenerative medicine. They are characterized by fascinating structural, optical, thermal, mechanical, electronic, and biological features, making them promising for various biomedical purposes. MXenes with high surface area, excellent conductivity, hydrophilicity, biocompatibility, high atomic numbers, and unique paramagnetic behavior have been hybridized with organic/inorganic materials to develop various biomedical devices, biosensors, tissue engineering scaffolds, antimicrobial agents, etc. Ongoing research in this field is expected to lead to the development of even more MXene-based biomedical devices in the future. Despite the biomedical potential of MXene-based composites, their biosafety and potential environmental risks need to be in-depth evaluated. In addition, physiological stability, decomposition rate, and controlled/sustained drug release as well as limited in-vivo studies and systematic guidelines are crucial aspects that should be considered for developing next-generation multifunctional MXene-based composites in biomedicine. Notably, clinical translation studies ought to be systematically addressed before these materials can be used in clinical applications. Despite their promising potential, challenges remain in the large-scale production and functionalization of MXenes. In this perspective, important challenges for in vivo applications, pitfalls, and future outlooks for the employment of MXenes in biomedicine are deliberated. The progress and biomedical applications of MXenes have been briefly reviewed, and the development background of MXenes has been introduced.