Compared with zero dimensional, two dimensional and three dimensional nano-materials, one dimensional nano-materials have superior gas sensing properties. In this paper, one dimensional ZnFe2O4 nano-fibers were prepared via electrospinning method using Zn (NO3)2? 6H2O and Fe (NO3)3? 9H2O as raw materials. The precursor was analyzed by TG-DSC, and the as-prepared samples were characterized by XRD, SEM, TEM, FTIR, nitrogen adsorption and XPS, respectively. The gas sensing properties of the as-prepared samples were investigated. The results showed that ZnFe2O4 prepared at 500oC exhibited nano-fiber morphology; it was revealed that the sensor device based on ZnFe2O4 nanofibers prepared at 500?C exhibited excellent selectivity toward acetone at the operating temperature of 190oC, the ratio of S1000 ppm acetone to S1000 ppm ethanol reached 8; when the concentration of acetone was as low as 1 ppm, the response was still able to reach 1.1.