Nanosized Ni3(Fe(CN)6)2(H2O) was prepared by a simple co-precipitation method. The electrochemical properties of the sample as the electrode material for supercapacitor were studied by cyclic voltammetry (CV), constant charge/discharge tests and electrochemical impedance spectroscopy (EIS). A specific capacitance of 574.7Fg−1 was obtained at the current density of 0.2Ag−1 in the potential range from 0.3V to 0.6V in 1M KNO3 electrolyte. Approximately 87.46% of specific discharge capacitance was remained at the current density of 1.4Ag−1 after 1000 cycles.