Pristine and Ag nanoparticle modified TiO2 nanofibers were fabricated by an electrospinning technique using polyvinyl pyrrolidone (PVP) and tetrabutyl titanate as precursor. The morphology and structure of the as-synthesized nanofibers were characterized by scanning electron microscopy and X-ray diffraction. It was found that the presence of Ag had a significant effect on the morphology and crystal structure of TiO2 nanofibers, and that Ag addition could promote the phase transformation from anatase to rutile. H2S sensing properties of the sensors based on TiO2 nanofibers were also investigated. The results showed that Ag/TiO2 nanofibers exhibited better gas sensing performances than pristine TiO2 nanofibers and the possible sensing mechanism was discussed. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.