Nanofluid has attracted the attention of many scholars for the excellent heat transfer enhancement capacity. In addition, electric field can further strengthen the nanofluid's ability of heat transfer. The thermal conductivity enhancement rate of nanofluid under electric field was studied using transient hot wire method under different electric field intensities, temperatures and particle concentrations. The influences of those parameters have been discussed. Besides, based on the static thermal conductivity and the dynamic heat conduction coefficient, a novel prediction model was established, which had a good agreement with experiment data. The mechanism of thermal conductivity enhancement under electric field was analyzed according to the prediction model. (C) 2016 Elsevier Ltd. All rights reserved.