The electrospun fumarate ferroxane/polyacrylonitrile (Fum-F/PAN) nanocomposite nanofibers were prepared by immersing the pristine electrospun (PAN) nanofibers into the solution of Fum-F nanoparticles. The synthesized Fum-F nanoparticles were characterized using FESEM and FTIR. FESEM micrographs revealed the smooth surface of the pristine PAN nanofibers and the decoration of Fum-F nanoparticles on the surface of electrospun Fum-F/PAN nanocomposite nanofibers. The electrospun Fum-F/PAN nanocomposite nanofibers were evaluated in order to remove lead from aqueous solution. A central composite design (CCD) and response surface methodology (RSM) were applied to analyze and model the obtained adsorption data. The applied variables consisted of lead ion concentration, adsorbent dosage, pH solution and contact time which maximum lead removal percentage of 97.89% was achieved at initial concentration of 30.30 ppm, adsorbent dosage of 2.06 g/L, solution pH of 6.18 and contact time of 68.23 min. The lead adsorption data onto the electrospun Fum-F/PAN nanocomposite nanofibers were adjusted well with Langmuir isotherm model, indicating the interaction between lead molecules could be assumed negligible. The maximum adsorption capacity of lead ions was 357.14 mg/g which was much higher compared to the reported values of other functionalized PAN nanofibers adsorbents. Reusability study of adsorbent confirmed the durability of removal even after five cycles of adsorption-desorption. (C) 2017 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.