The one-dimensional hollow cylindrical carbon nanotube nanostructure has been crucial in advancing nanotechnology since its discovery. Carbon nanotubes have been utilized in technical fields both in their pristine form and as nanocomposites. They have been combined with various conductive and non-conductive matrices based on specific end goals. In sensing technology, remarkable progress has been made in the development of multifunctional carbon nanotube nanocomposites. Common matrices used in this context include conjugated polymers such as poly(3,4-ethylenedioxythiophene): polystyrene sulfonic acid, polyaniline, etc., along with thermoplastics like polyamide, polyurethane, etc. Within these matrices, carbon nanotubes can establish a percolation network for electron or charge transport and can also create interfacial interactions to enhance compatibility, stability, and durability. The sensing capabilities of the resulting carbon nanotube nanocomposites are influenced by their interactions with the analyte, whether it be gases/ions, biomolecules, or motion. As a result, nanocomposites have been employed in the creation of effective gas sensors, strain sensors, and biosensors. The performance of carbon nanotube sensors has been evaluated based on factors such as sensitivity, selectivity, detection limit, reproducibility, and responses to analytes.