The invention relates to equipment and a method for preparing a nickel-base hydrogen storage alloy containing rare-earth, magnesium and boron and belongs to the field of smelted alloys. The equipment comprises a smelting-pouring tank, a lifting-stirring mechanism, an induction smelting furnace, a crucible, a pouring mold, a pouring mold driving device, a slide and a cooling water circulating system, wherein the smelting-pouring tank communicates with a shielding gas injection device and a vacuum pumping device. After an alloy is smelted, shielding gas is injected into the smelting-pouring tank under the vacuum condition and is pressurized, magnesium blocks are added under the high pressure and are quickly stirred, after melt is prepared, the pouring mold is cooled, and pouring is performed. The alloy prepared with the equipment and the method is stable in quality, compact in structure and small in composition segregation, requirements of further processing are met, the equipment is easy to popularize and suitable for large-scale production of the nickel-base hydrogen storage alloy containing rare-earth, magnesium and boron, and the material yield is high.