NOVELTY - A rare earth metal-magnesium-titanium-nickel-cobalt-aluminum based AB2 type hydrogen storage alloy electrode comprises lanthanum-rare earth metal-magnesium-titanium-nickel-cobalt-aluminum compound.    USE - Rare earth metal-magnesium-titanium-nickel-cobalt-aluminum based AB2 type hydrogen storage alloy electrode for use in a hybrid electric vehicle nickel metal hydride battery (claimed).    ADVANTAGE - The hydrogen storage alloy electrode has improved electrochemical hydrogen storage properties of the alloy, maximum alloy discharge capacity of 435 mAh/g, theoretical discharge capacity of 92% by 300 secondary electrochemical charge and discharge cycles and no significant hydrogen-induced amorphous phenomenon, and can be prepared with uniform quenched alloy flakes by using rapid quenching and annealing process.    DETAILED DESCRIPTION - A rare earth metal-magnesium-titanium-nickel-cobalt-aluminum based AB2 type hydrogen storage alloy electrode comprises lanthanum-rare earth metal-magnesium-titanium-nickel-cobalt-aluminum compound (La(1-x)RExMg(1-y)TiyNi(4-z-m)CozAlm), where the A-side elements in the compound is La(1-xRExMg(1-y)Tiy, and the B-side element in the compound is (Ni4-z-m)CozAlm), where x, y, z, m is atomic ratio, the x is 0.1-0.4, the y is 0.01-0.1, the z is 0.1-0.3, the m is 0.05-0.2 and RE is cerium, samarium, yttrium, neodymium and/or praseodymium and devoid of other than lanthanum. An INDEPENDENT CLAIM is also included for a method for preparing a hydrogen storage alloy electrode, which involves putting rare earth element containing cerium, samarium, yttrium, neodymium and/or praseodymium except lanthanum into a vacuum induction furnace smelting alumina ceramic crucible, adding magnesium on the uppermost outer crucible, evacuating to 1x 10-2 to 5x 10-4 Pa, applying inert gas at pressure of 0.01-0.1 MPa and heating at 1400-1600 degrees C to obtain melted lanthanum-rare earth metal-magnesium-titanium-nickel-cobalt-aluminum compound liquid mother alloy, maintaining the molten liquid mother alloy under a protective gas atmosphere for 5 minutes, directly injecting into quenching treatment, through bottom of tundish nozzle, continuously spray dropping on the surface of the rotating water-cooled copper roll cooling under inert gas protection for 30 minutes to obtain a thickness quenched alloy flakes (100-500 mu m), where the quenched alloy flakes are columnar grain structure having uniform micro crystal, nanocrystalline and trace amorphous structure, putting the quenched alloy flakes into a vacuum heat treatment furnace, evacuating to 1x 10-2 to 5x 10-4 Pa under inert gas as protective gas at pressure of 0.05 MPa, heating to 500-900 degrees C, incubated 3-5 hours, cooling the furnace to 150 degrees C or less to obtain annealed alloy, mechanically crushing the annealed alloy with 200-mesh sieve to obtain alloy powder having a diameter of less than or equal to 74 mu m, mixing the alloy powder with a particle diameter of 2.5 mu m and carbonyl nickel powder according to mass ratio of 1: 4 at 35 MPa and pressing into cylindrical test electrode sheet with a diameter of 15 mm.