Samples of lanthanum-doped nickel hydroxide were prepared by electrodeposifion method. The structure and electrochemical properties of the samples were studied by X-ray diffraction and a home-made open three-electrode cell system, respectively. The results show that the deposition process of Ni(OH)2 and La(OH)3 is mainly controlled by electrochemical polarization, which makes it easy to form uniform fine crystals. In addition, La(OH)3 is not a separate phase and lanthanum ions are doped into Ni(OH)2 crystal lattices. When V(0.5 mol/L Ni(NO3)2)/V(0.25 mol/L La(NO3)3) was 9:1, the lanthanum-doped nickel hydroxide reached the highest discharge capability of 840 F/g with a good cyclic reversibility. The capability still retains 670 F/g when the discharge current reaches 1000 mA/g.