A new technique was proposed for preparation of LaNi5 powder by direct electrolytic deoxidation of solid La2O3–NiO mixture oxides in molten CaCl2–NaCl. Oxides pellets was sintered and used as cathode. High – density graphite was used as anode. Electrolysis was performed. Current change during electrolysis was recorded. XRD was used to analyse the composition of products. SEM was used to analysis surface and cross section of pellets before sintering, after sintering and after electrolysis. The preparation mechanism and the influences of sintering temperature and cell voltage on electrolytic deoxidation was studied. Results show that the optimum conditions to prepare LaNi5 are：NiO-La2O3（Ni:La=5:1）pellets are formed at 30MPa, sintered at 850°C for 5h, electrolyzed under 3.2V in CaCl2–NaCl melt at 850°C for more than 12 hours.