In this paper, polyacrylonitrile (PAN)-polyamidoamine (PAMAM) composite nanofibers were synthesized using electrospinning technique and their dye removal ability was investigated. The functional groups, morphology, total surface area and pore diameter distribution of nanofibers were studied by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), the Brunauer-Emmett-Teller (BET) and the Barret-Joyner-Halend (BJH) methods, respectively. Direct red 80 (DR80) and Direct red 23 (DR23) were used as the model compounds. The effects of adsorbent dosage, initial dye concentration, and solution pH on dye removal were evaluated. Kinetics and isotherm of dye adsorption were found to conform to pseudo-second order kinetics and Langmuir model, respectively. The maximum dye adsorption capacity (Q(0)) of PAN/PAMAM composite nanofiber was 1666.66 and 2000 mg/g for DR80 and DR23, respectively. (C) 2015 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.