Mg-9Li-5Al-1Zn-0.6RE alloy was prepared by vacuum induction heating. The microstructure and phases composition of the alloy were analyzed with optical microscope, scanning electron microscope and X-ray diffractometer. Then the effect of homogenization temperature on microstructure and mechanical properties of the alloy was studied. The hardness of samples under different homogenization temperatures was measured. The results show that, the alloy is composed of alpha phase, beta phase, Mg17Al12 and AlLi. RE added into the alloy is solved in alpha phase and beta phase completely. After homogenization heat treatment, the needle-like alpha phase disappears. With the increase of homogenization temperature, the shape of alpha phase is spherical-like first, then vermicular-like, and large block-like finally. The variation of the shape of alpha phase causes the hardness of sample to change accordingly. The most favorable homogenization temperature for microstructure and mechanical proper-ties is 150 V.
