The development of cost-effective electrocatalysts with sustainable activity for efficient water oxidation has been intensively investigated. Carbon nanofibers (CNFs) with nickel and iron can be synthesized through controlled electrospinning and subsequent pyrolysis processes to investigate the effect of metal content on the oxygen evolution reaction (OER). Following detailed physico- and electrochemical characterization, the metal-derived mesoporous structure of CNF, with pores of 39 nm in diameter, seems to provide superior active sites for more favorable OER. This observation suggests a new perspective that can be extended to the preparation of both nonnoble-metal and metal-free electrocatalysts for a number of alkaline galvanic and electrolytic energy cells.