Microstructural and mechanical characteristics of Mg-4Li-1Al, Mg-9Li-1Al and Mg-16Li-1Al have been investigated in the present study. Alloy microstructures have been observed by optical microscopy and mechanical properties have been investigated by tensile test and hardness measurement. The matrix phases of Mg-4Li-1Al, Mg-8Li-1Al and Mg-16Li-1Al are the α,α+β,β phases respectively, depending upon the alloy compositions. As expected From the crystal structure of the α and βphases, Mg-16Li-1Al shows the best workability and Mg-4Li-1Al shows the worst. Generally, the as-rolled alloys show bet: ter mechanical properties than the solution treated-aged alloys, which indicates that alloy weakening due to the recrystallization of deformed structure is more significant than alloy strengthening due to age hardening. Mg-9Li-1Al and Mg-16Li-1Al show slight age hardening behaviour at room temperature. The mechanical properties of the alloys are relatively stable with annealing at 60℃, but deteriorate rapidly with annealing at higher temperatures above 100℃.