Multifunctional electrospun (ES) nanofibers are successfully prepared from blends of poly((N‐isopropylacrylamide)‐co‐(N‐hydroxymethylacrylamide)) (poly(NIPAAm‐co‐NMA)) with NO(g)‐responsive 1,2‐diaminoanthraquinone (DAQ). Different compositions of poly(NIPAAm‐co‐NMA) are synthesized by free radical polymerization. The NMA content significantly affects the stability of the ES nanofibers in water and the NO(g) detection due to a change of the hydrophilic/hydrophobic characteristics. In addition, the fibers exhibit a significant volume (or hydrophilic/hydrophobic) change during the heating and cooling cycle between 25 and 50 °C, attributed to the lower critical solution temperature (LCST) characteristic of the thermoresponsive NIPAAm moiety. On the other hand, a distinct on/off switching of the optical absorption spectra and high color contrast on detecting the NO(g) are observed using the ES nanofibers of poly(NIPAAm‐co‐NMA)/DAQ blends. The high surface/volume of ES fibers enhance the sensitivity and responsive speed, compared with that of drop‐cast film. The above studies suggest that the prepared multifunctional ES nanofibers have potential applications in environmentally sensing devices.