Iron oxide particle-decorated lignin-based carbon nanofibers (IO-LCNFs) were fabricated from organic mixtures containing acetic acid lignin (AAL) together with ferric acetylacetonate (Fe(acac)(3)) via electrospinning followed by stabilization in air and carbonization in nitrogen. After the addition of Fe(acac)(3), IO-LCNFs showed different morphologies: Non-fused IO-LCNFs were obtained with diameters of 400-500nm; iron oxide nanoparticles with diameters of 30-60nm were exposed outside and well-distributed when sufficient amounts of Fe(acac)(3) were added. These carbon nanofibers were then used as electrode material for pseudocapacitor. It was found that the iron oxide particles enhanced the resulting electrochemical properties via reversible redox reactions. IO-LCNFs made from the composite nanofibers with mass ratio of AAL/Fe(acac)(3) of 80/20 [i.e., IO-LCNFs (80/20)] exhibited the highest specific capacitance, 72.1Fg(-1), at current density of 500mA g(-1).