NiCo₂O₄ arrays with two different morphologies were synthesized on nickel foam through a hydrothermal method followed by a calcination process. X-ray powder diffraction (XRD), scanning electron microscopy (SEM), cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) experiments were carried out to them respectively. Results show that the samples are pure NiCo₂O₄, cover fully on the surface of Ni foam and morphologies uniformity. Moreover, the electrochemical measurements indicate: the sample synthesized with hydrothermal solution ratio of alcohol to water is 1:6, exhibited an areal specific capacitance as high as 1.57 F/cm² at a current density of 3 mA/cm²; the sample synthesized with hydrothermal solution ratio of alcohol to water is 3:4, exhibited an areal specific capacitance as high as 1.28 F/ cm2 at a current density of 3 mA/cm². Furthermore, the sample synthesized in this paper shows robust rate capability.