Polytetrafluoroethylene (PTFE) ultrafine fibers mats were prepared by electrospinning of an aqueous PTFE dispersion and a small amount of poly(vinyl alcohol) (PVA) and subsequent heat-treatment. The influence of dispersions composition on the morphology of fabricated PTFE ultrafine fiber mats was investigated. The fabricated mats were characterized by attenuated total reflection-Fourier transform infrared (ATR-FTIR) and koniology tester. The results show that the PVA/PTFE mass ratio of 1:5 was suitable for the PTFE fibers formation. All the PVA in the electrospun PVA/PTFE mats was removed at 350 °C~390°C. The fabricated PTFE ultrafine fiber mats have the potential to be used as high-temperature filter.