Fabrication and characterization of fiber optic hexane sensor using pristine ZnO nanorods have been reported. ZnO nanorods were synthesized by hydrothermal method. The structural, morphological and elemental properties of the nanorods were analyzed using X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectrometer (EDS). The XRD results indicate that the nanorods were crystallized in hexagonal wurzite structure. The SEM analysis shows the rod like shape of the synthesized nanopowders. The fiber optic sensor probe was fabricated via clad modification technology. Further, the probe was subjected to different VOC gases at room temperature. Test VOC gas vapors such as ethanol, methanol and hexane were chosen to investigate the response behaviour of the ZnO nanorods. Noticeably, the sensor showed higher selectivity towards hexane along with the sensitivity of ∼6.5%. The plausible gas sensing mechanism is also discussed in detail. The splendid sensing properties advocate that the ZnO nanorods are promising candidate for hexane sensor. © 2019 Author(s).