Alloy materials have attracted increasing attentions because they possess superior electrical conductivity which can contribute to excellent electrochemical performance. Herein a dendritic Ni3C alloy material has been prepared by the pyrolysis of nickel acetylacetonate employing oleylamine as a reductant and 1-octadecene or octadecane as the solvent. The current–voltage curves indicating that the electrical conductivity of Ni3C is higher than that of nickel oxide. Electrochemical testing indicates that a high specific capacity of 390C/g is found in alkaline electrolyte at 0.5A/g, and deliver excellent rate characteristic as well as cycle life. The excellent electrochemical performance may be attributed to its high electrical conductivity and dendritic nanostructure that can promote diffusion of electrolyte ions. In addition, the AC//Ni3C asymmetric supercapacitor has been assembled at a cell voltages between 0 and 1.6V, achieving a maximum energy density of 37Wh/kg (at a power density of 0.3995kW/kg), and this manifests that the Ni3C alloy is a promising electrode material for electrochemical energy storage.