The NiO electrode material has been successfully synthesized by a facile and simple hydrothermal method with the subsequent calcination. Compared with the original work, we omitted the calcination procedure before the hydrothermal reaction. The prepared samples were characterized by scanning electron microscope, X-ray diffraction. The electrochemical performances were investigated by cyclic voltammetry, galvanostatic charge–discharge and cycle life. The result shows the similar morphology with the NiO that underwent the calcination procedure and an enhanced capacitance of 250 F/g at 0.5 A/g was achieved. Furthermore, the material showed excellent cycle-life stability after 2,000 cycles, indicating the great application potential in supercapacitors.