MXenes are nanostructures with unique characteristics, such as hydrophilicity, large surface area, strong metallic conductivity, strong ion transport capabilities, biocompatibility, minimal diffusion barrier, and easy functionalization, which make these compounds suitable for bioanalytical applications. These materials are formed of transition metallic nitrides, carbides, or carbonitrides. Owing to their unique properties, MXenes have gained interest in various fields, including sustainable energy generation, fuel cells, supercapacitors, electronics, and catalysis. The composition and layered structure have made MXenes particularly appealing to biosensing applications. They can be used in electrochemical biosensors because of their high conductivity and multilayered architecture, which ensure the retention of activity in immobilized biomolecules. This review highlights the application of MXenes in electrochemical and optical biosensors, identifying future requirements and potential in this sector, particularly in the development of wearable sensors and platforms with integrated biomolecule detection.