BACKGROUND: Nitrate is a potential harmful contaminant to humans, and widely detected in ground and surface water. The aim of this study was to accelerate nitrate reduction using chelating resin-supported Fe/Ni nanoparticles. RESULTS: The results of X-ray diffraction indicated that the presence of Ni can prevent the oxidation of nanoscale Fe-0 particles by O-2. The nitrate removal efficiency (98.3%) and the rate constant (K-obs = 0.0166 mg(-1) L min(-1)) using supported Fe/Ni nanoparticles were increased greatly compared with those using supported Fe nanoparticles (21.3% and 7.93x10(-4) mg(-1) L min(-1), respectively). The co-existing Cl- caused a slight increase in nitrate reduction by the supported Fe nanoparticles, but SO42-, PO43-, HCO3- and humic acid caused obvious inhibition of NO3- removal. Due to Ni catalysis, however, the effects of these co-existing anions and humic acid on nitrate reduction by supported Fe/Ni nanoparticles could be ignored, except HCO3-. Moreover, the Fe/Ni nanoparticles showed good performance for nitrate reduction in drinking water. CONCLUSION: The supported Fe/Ni nanoparticles were more reactive than Fe nanoparticles. The co-existing anions and humic acid showed less effect on nitrate reduction. The supported Fe/Ni nanoparticles have a potential application for nitrate reduction. (C) 2014 Society of Chemical Industry