Polyacrylonitrile (PAN) carbon nanofibres with diameters of 100–200 nm have been developed by electrospinning and subsequent carbonization process. The composition, structure, electrical conductivity, and electrochemical properties of the carbon nanofibres as electrode materials for vanadium flow battery (VFB) have been characterized. It is found that with the increasing of carbonization temperature, the electrochemical activity of carbon nanofibres toward VO2+/VO2 + redox couple is enhanced greatly. Particularly, the 1000 °C-carbonized nanofibres show excellent performance. The good behavior of the nanofibres carbonized at high temperature may attribute to the conversion of fibers inner-structure and the improvement of electrical conductivity. Compared with the traditional carbon fibers (TCFs), electrospun carbon nanofibres (ECNFs) carbonized at temperature of 1000 °C exhibit higher activity toward the vanadium reaction, presenting considerable potential for electrode application in VFB.