In this work, hierarchical nanostructures of nickel (Ni)-decorated carbon nanofibers have been obtained via a facile electrospinning technique and subsequent carbonization process for using as efficient catalysts of hydrogen evolution reaction (HER). During the carbonization process, nickel ions are reduced into Ni nanoparticles while polyimide nanofibers are simultaneously converted into carbon nanofibers. Moreover, the amount of Ni nanoparticles decorated on the nanofibers can be easily tuned by adjusting the content of Ni(NO3)(2)center dot 6H(2)O in the electrospinning solution. SEM and TEM characterizations of the nanocomposites show Ni nanoparticles are uniformly distributed on the surface or partly embedded in the nanofibers, endowing intimate interactions and efficient charge transport between the nanoparticles and conducting carbon nanofiber network. Therefore, a low overpotential of -0.17V and a high current density of 3.05mAcm(-2) at eta = 200mV are measured for the 8% Ni-decorated carbon nanofiber membrane, suggesting a relatively high catalytic activity for HER. This versatile and low-cost method may pave a way for fabricating high-performance metal-carbon nanocomposites for various applications. (C) 2015 Elsevier Ltd. All rights reserved.