The invention provides high-anisotropy magnetic memory alloy and a preparation method thereof, and belongs to the field of shape memory alloy. The alloy has the good mechanical property and the high magnetocrystalline anisotropy and is the high-anisotropy magnetic memory alloy which can generate recoverable strain by driving martensite for twin crystal boundary migration and reverse migration through external magnetic field change. The chemical formula of the alloy is NiCoAlLu, wherein x is larger than or equal to 38.6 and smaller than or equal to 39.7, y is larger than or equal to28.5 and smaller than or equal to 31.6, z is larger than or equal to 27.4 and smaller than or equal to 34.2, j is larger than or equal to 0.5 and smaller than or equal to 7, x+y+z+j=100, and x, y, zand j serve as the molar percentage content. Compared with existing materials, the second phase of the magnetic memory alloy has the micron Lu2Ni17 metal intermediate phase, thus, the magnetic memoryalloy has the good mechanical property and the high magnetocrystalline anisotropy and can be well applied to the fields of high-precision drivers capable of being used at the room temperature, actuators and the like.