The unique electronic and optical properties of carbon nanotubes, in conjunction with their size and mechanically robust nature, make these nanomaterials crucial to the development of next-generation biosensing platforms. In this Review, we present recent innovations in carbon nanotube-assisted biosensing technologies, such as DNA-hybridization, protein-binding, antibody-antigen and aptamers. Following a brief introduction on the diameter- and chirality-derived electronic characteristics of single-walled carbon nanotubes, the discussion is focused on the two major schemes for electronic biodetection, namely biotransistor- and electrochemistry-based sensors. Key fabrication methodologies are contrasted in light of device operation and performance, along with strategies for amplifying the signal while minimizing nonspecific binding. This Review is concluded with a perspective on future optimization based on array integration as well as exercising a better control in nanotube structure and biomolecular integration.