TiO2 nanofibers were synthesized by an electrospinning technique using polyvinyl pyrrolidone and titanium tetraisopropoxide as precursors. The effects of processing parameters including the precursor ratio, calcination time, temperature and atmosphere were investigated. The calcination temperature determines the TiO2 phases as either anatase or rutile. The diameter of die synthesized TiO2 nanofibers is not sensitive to the calcination atmosphere or die time. However, the surface microstructure of the synthesized nanofibers depends highly on calcination atmosphere. Calcination in an N-2 atmosphere produces smooth surfaces. In contrast, surfaces that are more granular evolve when they are calcined in an O-2 atmosphere. In addition, less Ti precursor in the electrospinning solution results in slim nanofibers.