Porous zinc ferrite (ZnFe(2)O(4)) nanorods with a diameter of around 50 nm and a length of several micrometers have been synthesized by a microemulsion-based method in combination with calcination at 500 °C. The morphology and structure of the ZnFe(2)O(4) nanorods and its precursor (ZnFe(2)(C(2)O(4))(3) nanorods) were systematically characterized by x-ray powder diffraction, transmission electron microscopy, field emission scanning electron microscopy and high-resolution transmission electron microscopy. The formation mechanism for the porous ZnFe(2)O(4) nanorods is also discussed. Moreover, the porous ZnFe(2)O(4) nanorods were applied in a room-temperature ethanol sensor and exhibited much better sensing performance than ZnFe(2)O(4) nanoparticles.