Due to an increasing demand for portable power sources, lithium air batteries have attracted considerable attention as promising energy storage devices due to their high theoretical specific energy densities. In this study, carbon nanofibers (CNFs) were synthesized via electrospinning with polyacrylonitrile (PAN) and carbonization for use as the cathode in a Li-air battery. The electrospinning time was varied to produce CNFs with different degrees of loading in an attempt to investigate the influence of loading amount on cyclability. The surface morphology was characterized by field emission scanning electron microscopy (FE-SEM). The as-synthesized CNFs consisted of a randomly arranged network of cylindrical nanofibers with high electrical conductivity values and large pore sizes. The CNFs with lowest degree of loading (0.233 mg cm-2), exhibited the highest electrochemical performance up to 130 cycles. This work demonstrated the existence of a linear proportional relationship between the degree of carbon nanofiber loading and the cyclability of a rechargeable lithium-air battery.