The hierarchical aminated polyacrylonitrile (PAN)/gamma-AlOOH electrospun composite nanofibers were prepared by a combination of electrospinning process, chemical modification and hydrothermal reaction. The obtained membranes were carefully examined by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The hierarchical aminated PAN/gamma-AlOOH composite nanofibers were proved to be good adsorbents toward Pb(II), Cu(II) and Cd(II) ions in aqueous solution. The adsorption process of the Pb(II), Cu(II) and Cd(II) ions could be described by Langmuir isotherm model and kinetics were found to follow the pseudo-second order rate equation. The maximum adsorption capacities of hierarchical aminated PAN/gamma-AlOOH electrospun composite nanofibers for Pb(II), Cu(II) and Cd(II) were 180.83 mgig, 48.68 mg/g and 114.94 mgig, respectively. The results proved that the synergetic adsorption effect between amine groups and gamma-AlOOH crystals contributed to the high adsorption activity of the hierarchical aminated PAN/gamma-AlOOH composite nanofibers. The obtained membranes can be potentially applied in heavy metal ions removal from wastewater effluents. (C) 2016 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.