Ag-doped LaFeO3 nanofibers are synthesized by electrospinning method. The chemical and structural characterizations of the composite nanofibers are performed with various techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM). Meanwhile, their formaldehyde (HCHO) sensing properties are investigated in detail. The experimental results indicate that the sensor based on the sample Ag-LaFeO3 shows excellent gas sensing properties to formaldehyde. The response to 5 ppm formaldehyde is 4.8 at the operating temperature and the sensors have good selectivity. The response and recovery time to formaldehyde gas is 2 s and 4 s, respectively. (C) 2016 Elsevier B.V. All rights reserved.